What keep you from running into the 1250 EGT defuel backdown on the Edge when pulling heavy or 1/4 mi?


What lets you pull that 16K load up 6% on a 100 degree day without eng temps budging, and a 250+ degree reduction in EGT?


What gets you 50-100 HP, and 4-5 psi boost without a hint of extra heat to worry about?


What is cheaper than nitrous and propane bottles and makes everything last a lot longer, using windshield washer fluidhttp://www.dieselplace.com/forum/smileys/smiley5.gif?


What has been around doing all this since WWII, and only costs $3 per HP?


Edited by: masterp2

unless you ran a lot of meth with that water i don't think you see 50-60 HP... maybe on a stock motor it nets more?


at our last dyno day Rick was running a good amount of 25% meth/water and got 14 hp (dmax). Scott with his big bad doge got 31 hp, although i'm not sure how much he was running.. Seems to help EGT's fairly well but i think the HP claims are a bit on the high side. i've gotten a bit interested in it lately but haven't been sold yet...


Nick

Scott was running two 625 nozzles with a 50/50 mix to get his 31hp. He also said you got less additional HP when running water/meth with a big HP tuner than you might get on a stocker.


I think 15-30 HP is a more realistic gain in HP, but the EGT reduction is considerable.


Doug

Good information. I have been reading non-stop, about this as a tool to control temps, while hauling big. Sounds very viable, especially when in a hot dry climate.


Doug, 2 635 nozzles sounds in the ball park. Were both guys using a commercial system? Do you know the injection points(pre or post turbo/CAC)? Pump PSI?


What I am really interested in is the effects WI can have on sustainability of power. Dyno runs are fine, but usually last a very short time, unlike real world work involving elevated heat soak intake temps, which occur over time. I believe some of the overheating situations that occur, are a result of heat soak, and thermal decay with constant high boost over 20. With intake located under the hood, temps rise over time, turbo charge temps reach over 350, as the cooling is just not there at some towing speeds. My feeling is, over time, HP decays without something to stop the intake air heat rise progression.

Enter WI.

What I would like to see is a dyno comparison, using 5-10 minute dyno runs, and compare the HP at the end of each run.


Yes, Nick that was assuming WW fluid, 30% meth. The best HP combo I have seen is 50/50. But I like the idea of using the stock WW reservoir for this application, though it would be a little small for towing in most cases, it will last 20 minutes on the dyno.


I am going to put together 3 prototype kits. So far I have sourced the pumps, nozzles are next. I am thinking of 2 stages, switched at 15-20 psi boost(work stage), and the 2nd by floor throttle position (race stage). 3-4 nozzles total.Edited by: masterp2

Why turn it on so late? By 15-20 psi egts are over 1250*F. I've got two stages with the first on by 5psi to stop egts before they get over 1250*F and a second stage set higher to keep the egts in check. I can keep egts under 1000*F till the water runs out.

Michael,


First off let me say I'm no expert by any means, but I have talked to several who I would consider very knowledgeable. The kit I have is the Snow Performance Diesel Boost kit with the Hobbs activiation switch. It's not a variable flow system, its either off or 100% on, and you control activation via an adjustable boost-activated Hobbs switch. This version of the Snow kit is oriented more toward racing than towing, but you can use it for both. The other version has a boost controller that is more adjustable. You can control onset via boost, and also vary the amount of water/meth injected. The variable controller costs more than the Hobbs version but can be dialed in based upon towing needs.


Two 625 nozzles inject a lot of fluid. I'm only running 1 625 now, and was surprised when testing just how quick it emptied a 2 quart resevoir. Unless you were using very small nozzles, I'm not sure three nozzles would be useful. For towing applications, the WW resevoir would give you a short supply of water/meth, I heard someone say 4 minutes of flow with two 625's. Snow offers an 8 gal tank that would be great for long trips towing, but you could definitely rig your own bed-mounted supply of any size.


Doug

Jake,


Thanks for sharing your experience. I don't see why you would have 1250 at 5 psi. I know that is not exactly what you said, just implied.


Hmmm, I use 5 psi going up my driveway. Don't see how it would be useful on a truck with a good CAC already. Just uses water solution to do what the vehicle already can do without it. I'm not criticizing, you have the experience. Do you use it for towing? Performance? I could see lowering pressure with a large tank. Edited by: masterp2

Thanks doug.


The snow is a well respected name. You did well. I am just too much of a creator to buy a commercial kit for this application, especially when they are priced between $350-$600. It is a very simple kit that pumps a lot of water, with less than efficient droplet sizes, the cost of trying to get all that water out under low pressure in only one or 2 nozzles.


I am designing a simple kit that is for towing and performance (2 modes). Not hard to do, and yes, smaller nozzles a must, if doing 2 duties. Say (2) 325's for towing, post turbo. Stages 2 kick's in at full throttle with (2) 325's at intake. Just playing around with that right now. Also looking at stage 2 being (1) 325 at intake, and one pre-turbo.


I need to strap down whether isothermal (vs adiabatic) compression across the turbo is even possible.


Edited by: masterp2

Nick, what was the humidity and temp on that dyno day?

Michael


I've used it for mostly performance and a little towing. I've worked on nozzles and tested them at my job. I've made pressure vs. flow maps for all my nozzles. Worked with different pumps and custom tanks. I run an 8 gallon in bed tank while a friend runs a 13 gallon under his truck. I can burn through 3-4 gallons a day commuting to work. I've been working on a variable controller for a little while.


You don't need to start at 5psi. Just what I've been running for testing. Usually starting around 10-12 psi is good.

Nick, what was the humidity and temp on that dyno day?





it was cool weather, maby in the low 70's/high 60's.. didn't seem like much humidity as we don't get much here...

Doug,


After further research, I underestimated the airflow of the d-max (as I underestimated the diesel as an air pump). I think 50 HP would be a good goal, with intake temps under ambient if done right. 3 or 4 325 nozzles.


Has anyone had better performance tuning these systems?


Jake, I am guessing, at 5 psi, you don't get a visceral head back push out of your system, since it comes in so early, but if you had an on-off switch you could run'er up to 15-20 and kick it in. Do you get "obvious" power? What flow rates have you played with? PM me on your controller project, would enjoy hearing what your design input variables are, what the output is, is humidity factored, etc.Edited by: masterp2

So few people do a good job of in-duct evaporation. It is not an easy task. Getting fine atomization (under 30 micro) and not shooting onto the other side of the duct is part of the most successful recipes. You can't do that with one or 2 nozzles at 100 psi. Not in a diesel.

I talked with Scott after his runs. I'm not sure what his temps were, but before water/meth they exceeded his guages limits around 17xx degrees. With water/meth they are within the limits of his guage, but I don't recall exactly what they were.


I'd love to see 50HP with the system, but Sanddragger only got 14HP running two 625's on a 25% meth mix with the TTS Extreme. Before dynoing he'd run 50/50 but he said it was pinging pretty bad. If the detonation could be addressed and a 50/50 mix run safely. I've heard that the returns on water/meth deminish as engine power increases. If this is true, then maybe a 50/50 injected at the optimal flow can possibly produce 50HP on an engines producing less overall HP.


Keep us posted on your progress. The thing I'm learning about water meth is that there are many different variables - hopefully testing can yield some strong combinations of additional power and lower EGT's.


Doug

Are you all monitoring intake temps, to gauge how much evaporization is occuring before the manifold? May also be an effective tuning tool. Ambient temp is obtainable, but not sure about the dyno setting, with little cooling.


Are you both misting the intake, or elsewhere?

There has been some talk on some other threads that are better attached to this one. So.....

Most of the inputs that would be useful for a smart WI system are already on the engine with the exception of EGT and maybe a humidity sensor (wet bulb). I have already hijaked the MAF and EGR sensors with a simple circuit and think that, with minimal pain, an infinatly variable rate system could be made. By using a PWM signal to a solenoid valve, nearly any flow rate would be possible.

All of our info HP wise so far is WOT on the Dyno. That does not translate will to partial, but heavy loading on the street. I don't expect we will see it either.

I see there is at least one system using boost as the only input for a variable rate. Is that really best? What I am looking for is ideas on what the "ideal" injection rate would be and then see if I can figure out what it would take to meter out that amount. I envision something similar to the throttle body injection on the gassers.

check into the Alkycontrol.com system. It's a variable rate system that taps into the MAP sensor (or any other 0-5 volt circuit). I know most guys in the diesel market tend to lean towards Matts systems, but I've talk alot with Julio at alkycontrol and he's a really great guy to deal with. He caters more less to the Grand National guys (http://www.turbobuick.com/forums/forumdisplay.php?).

The Snow system (matt) is used often because it is one of the few kits that has pump flow capacity for the TD. It uses 2-3 times more water than gassers. But it does so at the expense of atomization. As a ballpark I believe we will need 200 ml/minute at the low end of 15 psi boost and modulate up to 900 ml/min WOT. With an eye on humidity, it could be more.

I think we pass a ballpark 800 cfm air, WOT (someone check me on this). It is a matter of determining the desired intake charge air temp (compared to ambient) and then calculating how much water/alcohol can be vaporized in that air charge to achieve 100% saturation. The metering algorithm can be built from there, with some thought on where to place injectors, including a pre-turbo stage, IMO.

You have to watch the size of nozzles you use because they are rated for a certain pressure. When you inject at twice the pressure they are rated for (200+ psi), you effectivly double the out put. Thus a 325ml becomes a 650ml or so. Some out there are quenching the fire to much. I have effectivly run twin 733ml at full pressure, and showed no more power gain. Just alot more detonation with the same amount of mix (25% meth). It also tried to cycle the glow plugs because it ran so cool when I tried the same nozzles with a 50/50 mix. I have good success run it right at the inline manifold just before the intake to the motor. I run smaller jets at high pressure for good atomization which is a helpful key. If you run pre I/C, some water may sit in the I/C and you get a sudden gulp of unatomized water at a lower rpm when you punch the go pedal. If you run pre turbo you can sandblast the turbo blades with the jet stream. It will erode them quickly. I am putting custom Dmax kits together now at special requests. They do use the inline manifold, so if you already have this item it will be that much less if you do wish to go with the kit.

Pics?

SD, we would love to know more about your systems.

For the purpose of this project, her is some helpful knowledge on the nozzles flow relationship with pressure:

Volumetric flow rate varies with the square root of the pressure multiple.

Doubling the pressure will result in 1.41x the flow (141%). To double flow, you must quadruple pressure.

An example: Nozzle 1 flows 650 ml/min at 100 psi. What will it flow at 800 psi?
Answer: sq rt (800/100) x 650=1838 ml/min


This is important to understand when designing a system that uses nozzles that are flow rated at a pressure lower than what it will see. Also important to create any design pressure algorithms with this in mind. It's not simply linear.

I will comment on the turbo damage statement, and not disagree with you. When running a coarse mist in front of the turbo with too large a flow rate, impingement can(has) create(d) a hazard to the compressor blade. The particle sizes are over 100u (micron). Unfortunately, most of the damage comes from hack installations, where, at the extreme, a person uses the turbo to atomize the fluid with no nozzle at all. A coarse large nozzle running at low pressure will also dump 300u+ sized droplets on the turbo and impinge. The key is to only introduce a 10-20u mist, a "dry fog". Particles this small harm nothing and cannot be filtered by our air filter. It will not harm the turbo, any more than a foggy day will. If pre-turbo mist is used as the performance stage, at high boost, then the huge volumetric air flow will quickly dissipate and evaporate the smaller droplets. Just don't overinject pre-turbo. Inject only enough to see the compressor efficiency increase at high RPM's (this is the only real value of pre-turbo misting anyway). If I can figure out how to post a pic off my PC, I will show this in the next post.

This chart will help. The average DIY system at 100 psi has a SMA of 100u when using one or 2 nozzles of sufficient flow rate. Evaporation of the droplet is the critical factor in WI effectiveness. Larger drops take longer to evaporate. If it hasn't evaporated before it gets to the cylinder, water is wasted (for the purposes of charge density). The rate of evaporation is directly proportional to the surface area of the water (a linear relationship). a liter of 15u droplets has 10 times the surface area of the same liter composed of 125u droplets. What this says, indirectly, is that 15u droplets evaporate in 10% of the time it takes 125u droplets to evaporate.

Since time is of the essence with about 1 second to evaporate, this illustrates why so much water is wasted in 60-100 psi kits. Inevitably, a fraction of the water is vaporized when misting occurs post-CAC, and a lot of liquid goes to combustion (and liquid is not combustible). This is fine for EGT control though, just not much power there. If you want power too, you need to evaporate the fuel (methanol). This argument doesn't stop at charge density. As has been observed, the meth needs to be vapor to be a HP enhancing combustible fuel, the more the better. Liquid methanol just puts out the flame. You can drop a lit match in a bucket of diesel and all that will happen is the match goes out.


http://www.fluidproducts.com/images/new_pa1.gif


Qoting this website: http://www.fluidproducts.com/gasliquidreactions.htm

Controlling droplet size
Turning a volume of liquid into droplets requires energy. This can be pressure provided by gravity or a pump, or using a stream of compressed gas to pull the liquid apart. Either way, the amount of energy expended relates directly to the amount of surface area produced. Smaller droplets require more energy. (However in some cases you can generate smaller droplets using amore efficient atomizer without more energy. Spraying 10 liters of water through one large full cone hydraulic nozzle will produce much larger droplets than spraying the same total volume at the same pressure through a larger number of smaller nozzles. Smaller hydraulic nozzles are more efficient and will produce smaller droplets with no increase in energy consumption.)

The liquid itself has a huge effect on spray performance. Elevated viscosity levels or surface tension make the job much harder or even impossible. If this is a factor, there is no point in working on the nozzles until this problem has been minimized.

There are many tradeoffs to consider when trying to achieve a specific droplet size. Most of the time people ask us how to generate finer droplets so here are some common suggestions balanced with the downside:

Use the existing nozzle or a smaller nozzle and run at higher pressure. This is probably the easiest answer, assuming you have the appropriate pump capacity. Running the same nozzle at 60 psi instead of 40 psi will increase the flow rate and reduce the droplet size. A double benefit when trying to increase available surface area.

Take advantage of the efficiency of smaller nozzles and use a larger group. You will face more complex piping and increased clogging potential, but these can be overcome.

Use a nozzle design that gives intrinsically smaller droplets if this is still possible. A great idea since an equivalent capacity hollow cone gives smaller droplets than a full cone, assuming you don't need the full cone's spray distribution.

SD

We need more information on your manifold splice mod. What type threaded adapter does it have for conventional nozzles that have threads on the base (vs the tip)? I would like nozzles that have a threaded tip but had little luck finding them. Some close up pics of your thread arrangement would be helpful. I have seen the other pics you posted, just can't see the whole idea on how nozzles are adapted to it.

For those that like alternative fuels, I think port injection would be the best because the intake manifold is made of 3 parts (left, right & middle) with an apparent flow bias toward the DS head. I would bet that the few guys that have blown headgaskets from too much liquid propane or from too much water/meth have blown the DS headgasket because of too much liquid in the left cylinders (DS). Putting individual nozzles in the left and right intake manifold would allow the water/meth or propane to be sprayed into each intake runner for equal distribution of alternative fuels to each cylinder.

Would that allow sufficient time for evaporation to occur before the water was introduced to the combustion chamber? Masterp2?

I think that is a question for the ages.

Perspective:

The 6.6 takes 400 cfm compressed air, roughly 800 cfm through the filter. If this had to travel through a 3" hose it would travel 3 miles in a minute, or 270 ft in a second. If there is only an equivalent of 40 ft of 3" run under the hood, from filter to intake, that is 2/10th of a second. .5 sec if in 4" hose. My guess is that there is a lot of liquid droplets at combustion. But who knows without test data. However, without question, pre-turbo misting, as fine as practical, has much more time to vaporize (than post CAC) and must be considered if 100% saturation is a goal. I like both at the same time. Plus you just get a better turbo.

I know you are into cooling it. The consolation is that even droplets at combustion contribute to cooling. They will be vaporized at combustion which will lower EGT emerging from the cylinder, so it's not "bad" news. That liquid just doesn't aid HP increase.

Comes back to what the goal is:

Cooler intake air thus denser charge

or

Cooler Chamber/EGT.

Yes

You want it all..

Well the direct manifold injection would be great for chamber temp reduction and not build up gulp in the CAC. Post turbo would be great for charge density.

Guess we need both.

What I have seen is this. I get the best mist I possibly can (fine). The company I bought the nozzles from provided the info on volumetric flow rates at a given pressure. I get more cooling with the 50/50 mix because the alcohol content not only privides as an extra fuel, but wicks away the heat much better than just straight water. You get a power gain from the water as well because of the increased pressure it creats in the cumbustion chamber. Mister Tomac is correct. I would be nice to see individual port injection. I blew the P/S head gasket on my truck however. This would be the best way to go for close monitoring of the egts per cylinder and adjust for it in top performance mode. I try to keep it simple for the sake of everday usage and simple egt cooling. My pump will go to 280 psi with twin 325ml nozzles. That creats a pretty fine mist. You can almost see the power when were testing the systems and just shooting it straight out of the shop.

I buy the stock nozzles, then machine them to my specs and machine an adapter to fit them to fit my inline manifold or what ever else you want them to fit into provided there is enough room. I'm not into algorithms to much, but I do know what works and I make it so. I could talk about nodes and nanodes hermonics in the way the air passage flows, but the engine doesn't much care at this point. Besides, I think the flow rates for the nozzles are actually at 60psi any way.

My pump will go to 280 psi with twin 325ml nozzles. That creats a pretty fine mist. You can almost see the power when were testing the systems and just shooting it straight out of the shop.
Guessing you run the pump without a regulator or pressure shutoff? 280 is great. The one pump I have wouldn't last 30 minutes at that pressure. Then if a nozzle clogs....

So i was thinking of an affordable 800 psi pump with bypass. No more barbed fittings and low pressure hose.

I suppose pre-turbo nozzles can be mounted to the plastic after the MAF sensor, unless someone has a product for that.

Here is a film clip of 300 ml/min from 100 psi, each nozzle.


here (http://water.lovehorsepower.com/Videos/MR2/WI_SprayBoth.WMV)


This is without airflow through the conduit, but it shows the atomization and evaporation challenge, with most of the water recombining on the conduit, and running into the turbo in a stream (if it were a pre-turbo application). IMO, This is what is wrong with low pressure misting with high flow nozzles in a 3" conduit. Just my opinion, not shooting up anyones successes. I believe huge gains with less water are possible

After crunching some numbers, it only takes 70 ml/min to lower post-turbo temps by 100 degrees, assuming 100% evaporation. I think many people are injecting 600ml/min or more, with innefficient evaporation. That amount of solution is necessary because of the innefficiency.

What I would like to do is use 2 low flow nozzles (.4 ml orifice or less) pre-turbo, and 2 or 3 nozzles post-CAC. 2 simple manifolds, separately actuated.

The post-CAC manifold could be modulated.

The pre-turbo manifold kicking in under max conditions, the performance stage. Could be a combination of parameters, or a throttle switch of some type.

Thoughts, ideas, suggestions?

Hook a leaf blower up to the end of that pipe.

Right, and if located close enough to the turbo, there will be little pooling, but potentially damaging drop sizes. Pre-turbo needs small drop size and some pre-turbo evap, to reduce the size even more.


That's not my film clip, just clarifying.

Pre turbo will make short work of compessor impeller believe me.

I have a system in the works boys and last dyno on lly was 127hp, yes 127hp with bug washer fluid only. note crystal brand seems to work best. Slow to get all this done but custom pumps built to spec are not cheap or fast.

lly101

Can you be more descriptive? 127 HP is pretty impressive, what's your secret?

I think A big part of the success I've had is the nozzles as they look nothing like we have seen before and the high pressure pumps are defiantly a must. I am injecting over half a gallon a min wide open.

Pump pressure? Nozzle source/type? If I am asking offensive questions, just tell me to shut up. I am assuming you are not inventing a system to sell. If you are I apologize. PM if you like.

I take it lly101, that your system is fixed delivery rate.

Another tid bit. The meth reduces the surface tension of the water allowing a finer mist without droplets recombining. Above a critical concentration there is no additional reduction in partical size. For cooling, a very very small concentration of detergent would have a similar effect.

excellent Fingers.

On top of the turbo, what is the purpose of the black plastic hat that says "6.6 duramax"? Just curious as it looks to serve no purpose except possibly surge protection, expansion etc.

Resonance chamber. Helps reduce intake noise.

learned something today!

I am in fact working on a system that I home to release early in the new year. Fingers, that is correct on my current system but I am in the process of finishing a variable system that is on the fly adjustable

Look forward to it. Have you done any pre-turbo trials? Results?

Hand variable system I take it. I would be interested in helping you with some real time controls.

Master considering the damage to the turbo, pre turbo cooling will probably have to take the form of some sort of wick system. No water droplets to ingest.

Done correctly, there is no danger to the turbo. A fine mist that is not allowed to pool into the turbo is what is called for. That may require a lower flow rate, but that is what I had in mind anyhoo. 2 nozzles, .008" (smallest) under 800 psi will flow 150-200 ml/min with nearly no drops over 20 micron. If reserved for only the highest boost, I feel plenty comfortable with something like this on my own truck. If looking for the optimum performance gain, it does seem to be the ticket.

The turbo eats this particle size every day in dirt and dust which is tougher than water. It is a performance stage conceptually, hardly ever used, (the post CAC nozzles would be used for daily modulation) even if it were an impingement, it would be unlikely to show up unless you spent every day at the track, but I doubt even then.

Just my opinion after reading numerous accounts. Those that reported damage used crude techniques, 60 psi and high flow with the type of mist shown in the video (and worse), splashing into the turbo. The nozzles above would produce the lightest white fog. We have misting system here at restaurants, the ones that are highly pressurized make clouds, not heavy "mist". The drop size is so small they are suspended.

But unless I can affordably supply the 800-1000 psi, this remains to be seen. I will order a pump this week to test.

Here is something else to consider - The greater the temp difference between your compressed air charge and the air forced through the cooler by speed or engine fan the better your inter cooler works ... So if you cool the air before it gets to the inter cooler you now have greatly reduced its efficiency. Therefore I believe in post IC cooling with water atomization.

If all works like I have planned, my system will be adjustable and variable in relation changing engine conditions... boost, temp and others etc

Yep, naturally. And getting the help it needs both pre and post-CAC to lower charge temps. Let me clarify, again not shooting up anyones successes, and thanks for keeping this alive. Where I live, the air is so dry (mile high Denver is dry too with low air density) it can absorb 5-10 times the water that, let's say, florida air can. And getting the first 100 ml evaporated is a whole lot easier than the last 100ml, in any weather. It takes a lot of mixing, time and multiple injection points/stages IMO to approach saturation without overspraying to compensate for the lack of conditions necessary to efficiently vaporize (a conduit wall is not the ideal place to vaporize a mist) . This seems to be prevalent IN DIY, low pressure overspraying, with a lot of liquid going to combustion, well tolerated by the diesel.

If I were going to inject in only one place as a performance enhancement without considering possible damage consequences, pre-turbo is it. Doing so creates a lot more boost. However, If I only had my eye on intake charge temps, and could believe that I could saturate the air in that last .1 seconds post-CAC, then I'd go for post CAC, but only because people don't want to mist their turbos. I don't think that is possible, not enough time to get that much water evaporated IMO.

I believe that oz for oz, pre-turbo is a better performance alternative. CAC efficiency is lost when using pre-turbo misting, 1-5% with the moderate volumes I like. I am acknowledging that. That's not the end of the story. There is more to consider. Turbo efficiency (which sucks on the top end), reported to gain 10-20% due to denser cooler charge and pseudo isothermal compression. That's tough to knock. I can be sure that more total water can be vaporized this way (meth too-the fuel) vs post-CAC only, and more charge density resulting from the additional boost (free boost by the way, the turbo doesn't have to work for it since it results from increased efficiency and less adiabatic loss). Now on a 80% miami day, that's another story.

I am not inventing this, it was all done before me, fighters in WWII, B-52G's used 10,000 lbs of water among 8 turbines in 90 seconds (all atomized) for heavy 488K lb GW take-offs, pre-compressor. Today GE uses compressor water mist to net big output gains at it's generator plants. Those are multi-million dollar "turbos".

There is a guy doing a detailed study comparison on this right now, there will be some charted vehicle data on it soon.

Going back to the reason this thread started (WI as an overheat solution), some of the ongoing theory of the LLY towing overheats, is that the CAC is moving so much heat that the radiator can't get a break. If this is true, it may because of turbo efficiency problems, too much boost, whatever. Lowering the pre-CAC temps with pre-turbo misting, addresses that head on. Something to think about. Of course lowering egt's addresses it on the other side, keeping coolant T lower. Only pre-turbo misting lowers BOTH egt's AND CAC charge temps.

GE uses steam injection in the combined cycle gas turbine generators. They abandoned the direct compressor mist injection due to severe rotor blade errosion. I'll look up the reference.

I see GE is selling the SPRINT gensets w/ water mist injection. The injection tech is a bit different than a simple nozzle though. Also found horror story accounts from utilities, but the SPRINT system itself was not mentioned.

That would be interesting to see the details. They injected the rotors?

I still have all my B-52 manuals around somewhere. I'll have to see if it has a diagram of the rings and where they are placed.

From what I can gather, they use post compressor air (~500 psi) and inject it with the water into the injection rings at different stages. I didn't see any detail on configuration within the stage. They do not place it pre-compressor to cool ambient. 10%-20% increase in compressor efficiency. I wonder if the water is still droplets after exiting the nozzels?

Read another study, misting ambient, but they made sure all the water was evaporated prior to entering the turbine.

Keep in mind these are all axial flow turbines. I have not found anything yet on ambient injection for radial compressors.

You're reading, you're hooked. Share the links, in the event I haven't seen them yet.

Injecting water pre-compressor isn't going to work very well. all one needs to do is look at the pipe routine and the inside of an intercooler to know why. Look at what it takes to keep water in suspension and then what the pre compressor routeing does. Since moisture in the air stickes to surfaces like dew to a window what's going to happen here? The Hottest air will hold the most additional water content not the coolest!

Ok, I'll bite (west nile talk):

1 cubic foot of air at 100 degrees F, 96% RH (Bourbon street rainstorm)

1 cubic foot of air at -20 degrees F, 95% RH (N Dakota snowstorm)

Upon full saturation which parcel can hold more water in vapor state?

It's not about the amount of moisture in the air, it's about what happens to the air with moisture in it. I take it you have not looked at an intercooler very well (should of knowen)! The trick is to keep the moisture in the air not allowing it to come back out which by the way is what it does in the intercooler. So by injecting pre compressor you added mass to the air slowing the acelleration rate of the wheel then allowed the intercooler to take the moisture and turn it back to water dropplets and lowered the efficenty of the intercooler! Go ahead Masterp2............. just what's needed. You need to learn to look at the entire system and how it functions just not what's going on at one point within the system.

Now I finally know what I need to learn.

Can I go now? The "suspension" is killing me.

What keep you from running into the 1250 EGT defuel backdown on the Edge when pulling heavy or 1/4 mi?


What lets you pull that 16K load up 6% on a 100 degree day without eng temps budging, and a 250+ degree reduction in EGT?


What gives you 50-60 HP, and 4-5 psi boost without a hint of extra heat to worry about?


What is cheaper than nitrous and propane bottles and makes everything last a lot longer, using windshield washer fluidhttp://www.dieselplace.com/forum/smileys/smiley5.gif?


What has been around doing all this since WWII, and only costs $3 per HP?


Edited by: masterp2

IT ISN'T WATER INJECTION or WINDSHIELD WASHER INJECTION! :rolleyes:

Don't you have some Christmas lights to put up?

I use water/meth injection on my cummins and will be on my DMAX soon. The difference between 50 percent pure methanol and 50 percent distilled water compared to windshield washer fluid is night and day, you have to try both to really understand the difference. This is just from my experience driving with the two.

:confused: HELP ME UNDERSTAND WHAT U R TALKIN ABOUT...WHERE YOUR INJECTING WATER...AND WHAT FOR???:confused: :confused: :confused: :confused: THANKS FOR UR HELP

:confused: HELP ME UNDERSTAND WHAT U R TALKIN ABOUT...WHERE YOUR INJECTING WATER...AND WHAT FOR???:confused: :confused: :confused: :confused: THANKS FOR UR HELP
injecting high pressure water/methanal in a fine mist form post turbo which allows for cooler exhaust tempertures and allows more boost to enter cylinders, also adds in the combustion with the methanal/water acting as another fuel, reading the last 7 pages, and the other two threads on this will fill all the answers you are looking for, looks to be a good idea for lowering temps with a added power bonus:ro)

Still Dont Understand How Lowering Exhaust Temp After Turbo Will Increase Hp....just Cant Seem To Be Able To Wrap My Head Around This One Thanks For Reply

I does work. We just need to fine tune it. I have some guys from Europe helping me because they have been using it for years.

Guess you don't need my help. I'll go play in my own sand box.....

DURATYS,

They are talking post turbo on the intake side. Not post turbo on the exhaust side.

Water when injected in the right quantity and in a fine plume will help to cool the combustion chamber. The methanol mixed in will help to make more power.

Water injection has been used by the tractor pullers and big sled pullers for years. Especially when the motor/turbo combination in question has no intercooler(CAC).

Water/Meth is my next progression. I built my own system for my Cummins, and will probably do the same here using what I learned from the last one. I've built over 20 water/meth systems for myself and friends and am happy to tackle this one too.

Let's get it done boys. This stuff is fun to play with. I just need a little time to work n my own rig. Doing everybody elses stuff tends to slow me down.

This latest project has been hell. We've been rying to put compund turbos on a 6bt in a Dakota and its kicking my butt. We'll probably use water because fitting A/C and an intercooler isn't easy when ou stuff a Cummins 6bt in a dakota without moving the firewall. So rather than put the intercooler in a bad location or spend a ton on a custom intercooler we're resorting to water.

Since everyone is off doing their own thing, lets talk suppliers. Where are you getting your pumps, injectors, lines, controls........ Do you have a custom part others would be interested in?

With time, tech and technique will converge into a proven design(s). The "tested and failed" group will also grow. :) Pissing in each other's Corn Flakes isn't going to get anyone anywhere.

Depends. I ran out of milk this morning.

With time, tech and technique will converge into a proven design(s). The "tested and failed" group will also grow. :) Pissing in each other's Corn Flakes isn't going to get anyone anywhere.
Water injection has been around for years and does work for it's intended purpose.

IT'S NOT what Masterp2 is trying to lead people here to believe!

It's job is to cool the intake air charge temperature, nothing more nothing less. The problem has always been how much water to inject. A perfect setup one day is not on another day so everyone runs at less than the desired amount to be safe. To truly control the water you would need to know the condition of the air you are going to inject the water into and adjust the amount accordingly. In theory pretty basic stuff but in practice pretty tough job. Adding Methanol instead of water, or a mix of methanol and water does the same thing but the more the methanol the greater the cooling affect and thus the greater power achieved. A methanol injection unit will always out perform a water injection unit, period!

One thing to worry about is the amount of storage you will need to run a system. A typical race tractor will use about a 1/4 gallon during a pull! One pull is about 20 seconds run time on those tractors. Now in an over the road vehicle you will use less but pulling a grade may take as much as 10 minutes out west here and that will consume around 2 gallons of injection material, so a large tank is needed. Finding a place to put the tank is just one of many issues for an over the road vehicle. Then what happens when it runs out?

Like I said before it has it's place and for racing it works out great but it's never going to be the end all be all that Masterp2 said in the beginning of the thread.

See Fingers. I was just getting thirsty. Anyone who care to read the tranny thread in my sig will see what is going on here.

A practical use for over the road is the reduction of EGTs to "acceptable" levels. That would be one of my goals anyway, and is what got me involved in this thread in the first place. I had in mind an EGT sensor input that would regulate the amount of water injected. From what I have gathered here, the amount of water needed to do that is much lower than the big boost Super Diesel injection rates. So bracketing the injection rates needed to control EGT for nearly all conditions seems plausable to me.

Any further thoughts on a humidity input Fingers? It may not be that important of you decide on post-CAC only. I am thinking it carries more value for a partial pre-turbo fog. Sounds like you are going your own way.

In the name of KISS, pre and post injection temp sensors, MAF for scaling. For a known injection rate/ MAF you have a predictable temp drop for a given RH. If you do not get the expected drop, you are over injecting. Greater drop indicates under injection. This works for any RH. Post injection sensor needs to be in the transistion zone to give you a good indication of the evaporation rate.

Prostock & Superstock tractors use way more than 1/4 gallon of water on a 300' pull.

So a system like Fingers is talking about, would you PWM the pump to control pressure with a fixed orifice with a single NC solenoid or would you PWM the solenoid using a fixed pump pressure and a fixed orifice? I have seen the systems both ways.

The system I have been playing with PWM the pump referenced off of boost (ties into the 0-5 volt MAP signal). It has adjustments for turn-on point and injection rate. Minimum pump pressure starts at 100psi runs up to 220psi depending on requirement.
I have yet to install the data recorder on it to see what line pressure is through out it's range. Looking to do that this weekend.

This is all still on the bench in testing.

Prostock & Superstock tractors use way more than 1/4 gallon of water on a 300' pull.This is correct. A Grand National level Prostock (or Diesel Super) will use approximately 3 gallons of fuel (0.9cc/strk X 6 cylinders X 5000 RPM X 45 seconds) and 1.25 gallons of water.

The pullers that I know are using strictly port water injection using a Simpson (boost controlled variable) system. Recently, another system that has made its way onto the track...

http://www.scheiddiesel.com/waterinjection.htm

This might be something for the truck guys here to look into..?

Regards,

It would be helpful to know what the MAF sensor (that thing on the filter box) tells us. Is it an accurate measure of mass flow, velocity only etc.?

Not sure which would be more useful for mist modulation, MAP or MAF voltage.

I think Fingers wants to modulate a solenoid, but I question it. For OTR cooling and long pump cycles, I would think modulating the pump with duty cycle would keep it cooler (and that is going to be a challenge in this beast) but I am unsure. Finding a high pressure pump manufacturer that will talk to you with 140 F ambient exposure has proven difficult. Some of the Shurflo pumps will stay somewhat cool, but only deliver 140 psi.

Provided the pump can handle no flow, I would PWM the solenoid. Near instant response and micro fine predictable adjustment of the flow throughout the range. PWMing multiple injectors in a staged fashon has the advantage of always keeping the pressures within the optimal operating range for each injector. No pisssers at low flow

What I see as a problem with the boost only systems (And I may be talking from ignorance of some issue) is that boost does not tell you how much air is actually being injested. I can see it as a trigger for starting injection, but 2200 RPM and 32 PSI boost is way less air than 3000 RPM and 32 PSI. The MAF sensor will give you a nearly proportional signal for how much air is actually being consumed, and thus (this is where I am probably wrong) how much water can me added.

Well this thread has certainly livened up over the past week! Good to see the wide variety of opinions. Nobody has "hit the nail on the head", "hit the ball out of the park", "put this baby to rest" ):h but whether you realize it you guys are circling the wagons a bit tighter every time you engage each other on the technical aspects of WI. Impressive! :)

From what I read on all the WI links MP2 provided WI not only reduces EGT's but increases hp, provides better lubrication to cylinder walls, reduces intake temps, etc. If I recall correctly some applications do use it both before and after combustion. LLY101, sounds like you are almost to an application stage, very interested to see your results. :ro)

I was thinking, I drive by a power plant on the way home and usually see what appears to be steam coming out of the stacks. Is this WI being used to cool the stacks? :confused:

Keep up the good work guys. Personally I would like a system that just "takes the edge off" during normal driving, but when towing heavy in hot weather at high altitudes I can "put the h20/meth to it and hold on! Not looking to race my truck. JJ :)

The only problem useing the MAF for high Hp applications is that it is out of range for anything over 2500 rpm. So for simple purpose of cooling a fairly stock application it will work fine but anything like a HJ, TTS Xtreme, Big VA box your out of luck. Using pre and post temp sensors will help but you need to look at the responce time of the sender and the air flow rate.

I am assuming that you are saying the MAF voltage signal peaks around 2500 RPM?

I am not familiar with MAP (manifold atm pressure), but isn't that an accessible signal that is tell all on mass flow?

Sounds like it is time for a competition of sorts. Who can come up with the best stock modification WI system using WW fluid? Each forum participant put $500 on the line. Could be a tidy purse. Let's say for June.

That would bring you back to a boost/RPM calc. Fairly simple circuit to combine the two intellegently and get a proportional MAF type signal with a known error factor. Harkens back to the early PCMs and the problems they had temp variations.

You could kill two birds by oversizing the intake tube and correcting the MAF signal for the ECM. (our MAF is only a local flow rate (velocity) sensor) The raw MAF signal would now be scaled to fit while getting a huge intake. Hmmm.

I am trying to avoid using an actual programmable module. At some point, however, it would be the way to go if the mapping between sensors and injection gets complicated.

I am assuming that you are saying the MAF voltage signal peaks around 2500 RPM?

Appears to be the case

I am not familiar with MAP (manifold atm pressure), but isn't that an accessible signal that is tell all on mass flow?

MAP sensor = boost sensor

Sounds like it is time for a competition of sorts. Who can come up with the best stock modification WI system using WW fluid? Each forum participant put $500 on the line. Could be a tidy purse. Let's say for June.

Pass. I already give my work away and couldn't cover the entry fee. :))

I was thinking, I drive by a power plant on the way home and usually see what appears to be steam coming out of the stacks. Is this WI being used to cool the stacks? :confused:
JJ, is the power plant a coal burner? If so, they use a scrubber to clean the smoke. They spray alot of water through the smoke to precipitate the ash. Also, alot of steam comes from the cooling towers which condense the steam back into water after going through the turbines.

Yeah they are coal burning plants. All the talk about WI being such an efficient coolant got me thinking about how hot those stacks must be. Didn't want to get WI off track, just a thought. Thanks Marcdeluca. JJ

Just a thought for those of you who are looking for storage space. It's a 20 gallon tank. Remember, my truck doesn't have an IC and since I tow, I use quite a bit of water.

nice. I was going to ask you how you keep so far off the overloads, then I saw why, oops!

Do what the P51's do and spray (ice cold) distilled water on the intercooler.

Had thought of that problemchild. Because of space, I would have to spray in front of the condenser. So it would really ice down the AC, but have much reduced effectiveness on the CAC if liquid water doesn't come to rest on the CAC fins. (I am using CAC-charge air cooler vs IC, don't mean to be confusing.)

I see the subaru WRX is closer to a rally car now. It has a factory mister for the IC. The company says it gives it up to 5 HP.

I've experimented with an iced water/meth solution and wasn't able to discern much of any real performance improvement. Too much trouble for whatever gain, IMHO.

Evaporating the water mix (state change from liquid to gas) absorbs the equivalent energy of 500 degrees of liquid temp change. So if you could ice it down 50 degrees, it is still has only 10% of the effectiveness of evaporating the water, iow you can add 10% to water injection effectiveness by using 32 degree water. Yeah, too much trouble.

Humor me.

What is the expected increase in charge density by evaporative cooling?

Now, considering you have added water vapor to the charge, what, if any increase is there in O2/charge in the new, denser charge.

you are going to make me work now? Are we back to internal misting?

Can I site a paper instead? These are the tough questions.

I want some one else to check my math. Either I am doing it wrong, or we are all off base on what role water is playing.

You *may* piss off some tracks if you are doing external misting on the IC. Most joints dont like water dripping were people are launching. I am not sure if you guys are at internal or extrrnal disscucion now?

Math? I have to do math? A little humor.

I was a pilot in the Air Force, i once had a Navigator whos favorite line was:

N-"Pilot, Nav?": P-"Go ahead": N-"Can you please tell me where we are? I have a right to know"

http://not2fast.wryday.com/thermo/water_injection/water_injection.shtml

http://not2fast.wryday.com/turbo/glossary/turbo_calc.shtml

seems to have a good grasp. Be aware, the calculator has no evaporation limits, it does not seem to know when 100% is reached. Hope it helps to verify your calcs. I'll try to find a good explanation for the 02 dispacement phenom.

http://www.aquamist.co.uk/info/documents/turbowhitepaper/title.htm

another good read.

Another flood of information for understanding the big picture. Not too technical.

here (http://homepage.ntlworld.com/johnnya/max-boost/)

Fingers, are you using a complete charted steam tables? My book is in the mail, so I don't have them in front of me, but I realized I needed them (I sold the Chem E reference book, never thought I would be using it again)

http://www.engineeringtoolbox.com/28_101.html

http://www.engineeringtoolbox.com/24_162.html

http://www.engineeringtoolbox.com/28_457.html

Don't know if this will help.

ratlover makes a good point. I've been assuming all along that we are talking about internal misting; just prior to the intake manifold. I hope the the following source, which speaks to the displacement of oxygen in the cylinder, isn't a rehash of previous info.

Water Injection

Water injection (and water mixtures like mixed methanol injection) has been around for decades. Its sole purpose is to suppress engine knock. Keeping in mind that most engine knock is caused by uncontrolled and/or unintended combustion of the fuel mixture. Water with it high specific and latent heat is an excellent tool for bringing charge temperatures and combustion back into control when charge and cylinder temperatures or compression get too high for the fuel being used. Consider the following table from ERL / Aquamist:

http://www.aquamist.co.uk/info/images/wateri2.gif
**Source: Aquamist MF2 Manual

This table illustrates very clearly why water or a water/methanol mix should be used for induction charge and in-cylinder cooling rather than using excess gasoline. Water has over twice the specific heat of gasoline and more importantly to its application of gasoline has over six time the latent heat of evaporation that gasoline does.

To give you an idea of exactly how much work needs to be done, the following charge temperatures measured at the turbo outlet in an Aquamist study are very illustrative:

http://www.aquamist.co.uk/info/images/adiabatic.GIF

Effect of water injection in the induction system:

Water is generally introduced to the induction system after the turbo-charger and before the throttle body (unless multi-port water injection is being used, which is more complicated than this paper contemplates). It may be injected pre- or post-intercooler or both.

The injection of water into the induction charge will immediately absorb heat from the charge thereby increasing its density. Evaporation of the water at this point is unlikely or very minor. The induction charge can at a maximum reach 100% relative humidity and will stabilize at an equilibrium state that is governed by temperature of the charge exiting the turbo and the relative humidity of the ambient air. At full saturation the induction charge will have a significantly reduced temperature somewhere between the ambient temperature and the temperature of the injected water. This heat absorption is achieved primarily through the water's specific heat very little vaporization will occur at this point. The boiling point of water is higher than most charges exiting the turbo and the cooling effect of the water will reduce even the hottest charges without significant vaporization and never beyond the point of saturation and equilibrium.

Look at the density losses from heated induction charges (which directly works against the objectives of forced induction) and the improvement in charge density from various temperature drops again from Aquamist:

http://www.aquamist.co.uk/info/images/p-ratio.GIF

http://www.aquamist.co.uk/info/images/tdrop.GIF

The effect of water on the induction charge will be somewhat greater in drier climates where more water can be evaporated into the air. However this should not be taken as an indication that it is not useful in more humid climates. Once the induction charge gets heated it will always have room to accept the evaporated water whether the initial relative humidity was high or low - and this evaporation will always absorb heat from the induction charge.

As the water absorbs heat the droplet sizes will decrease and the surface area of the water droplets will increase. Any additional volume from this reaction will be more than made up for by the reduction of the charge temperature and its resulting increased density. Water is not displacing the volume or weight of air in the induction charge and actually working to increase the volume and weight of air that reaches the cylinder. Sizeable droplets of water will reach the cylinder with significant heat absorbing potential intact.

The cooling of the induction charge is the first way that water injection suppresses knock and permits more air-fuel mixture to enter the cylinder.

Effect of water injection while entering and in the cylinder:

During the intake stroke as the induction charge passes the valve the charge picks up heat from the heated surface of the intake valve. Additionally the effort of sucking the charge past the valve transfers heat to the charge as well. The presence of water in the induction charge absorbs this heat more readily with a lower increase in the temperature of the charge. Remember that it takes more heat to increase the temperature of the water present in the charge. Air and fuel alone in the charge increases in temperature much more readily and rapidly as it absorbs the heat from the valve and effort exerted to bring the charge into the cylinder.

*Thanks to hotrod on NASIOC for pointing out the starting basis for the conclusions reached here.

Once the charge enters the cylinder, water in the induction charge following the exit of the super heated exhaust gases (1500+ degrees) begins to immediately cool the surfaces within the cylinder including the cylinder walls, piston head, combustion chamber, valves and spark plug tip. This cooling will have its most dramatic effect on any possible hot spots the coolant system has not adequately addressed. Surface temperatures will be significantly reduced by the water even more so than the extra fuel that was previously being used to cool the cylinder surfaces.

With twice the specific heat and six times the latent heat of gasoline, 1/6 as much water by weight is necessary to fully replace the heat absorption of the decreased gasoline in the induction charge. Richer than 12:1 none of that extra fuel is being burned in combustion and the extra fuel robs significant power while serving as a poor coolant. Since the amount of water being added is only a fraction of the amount of the decrease in gasoline there is actually more air and as a result more oxygen in the induction charge for additional combustion to take place.

The cooling of the cylinder area surfaces permits additional air/fuel mixture to enter the cylinder thereby increasing volumetric efficiency. The combination of decreased liquids in the induction charge combined with the increased VE from in-cylinder cooling disproves the myth that water injection will displace air in the induction charge or reduce the amount of fuel that will be burned in combustion.

During this process the continued absorption of heat will decrease the water droplets further increasing their surface area and volume but full vaporization accompanied by the resulting 1700 times increase in the volume of the water will not have occurred at this point. The water will still reach equilibrium prior to this point, albeit in a hotter state.

The absorption of the heat gain while actually entering the cylinder and the cooling of the cylinder area and volume is the second way that water suppresses knock - the cylinder and the charge is much better prepared for a controlled burn during combustion.

Effect of water injection during compression and combustion:

By this time water has lodged itself between the air/fuel mixture although the percent of water to the mixture is only around 1%. Though the ratio is small the water further suppresses any remaining tendency of the fuel to pre-ignite by lodging itself between the air and fuel during compression. Before actual combustion occurs the water works against auto-ignition by continuing to absorb the heat generated during compression.

Water is a byproduct of combustion it is the chemical reaction of oxygen with the hydrogen freed from the hydrocarbon chains during combustion. How could the injection of additional present water before combustion contribute further to the combustion process? This is where it gets a bit complex and I will try to do the best I can. This pieces together various pieces of my understanding from different sources.

During early combustion when the fastest reactions occur the effect of the water in the mixture is to cause a more controlled and stable flame front. The freeing of hydrogen and carbon to combine with oxygen has to work around the present water to form OH radicals and CO. By slowing this early combustion process there is further suppression of the potential for the mixture to burn too fast and contribute to knock.

Later in the combustion process slower and more complex reactions occur. The formation of OH radicals is very fast and interferes with the completion of the combustion process to form CO2 from the first step creation of CO. It is during this phase of combustion where present water helps to complete the slower reaction to complete the formation of CO2 since water is about the only way to complete the oxidation of CO. The additional present water actually speeds this reaction which also happens to be when as much of two thirds of the energy from carbon combustion is released.

* Sources: Bob Harris note on DIY_EFI thread (http://not2fast.wryday.com/thermo/water_injection/water_chemistry.txt) and the reference within to Combustion, Third Edition by Glassman (reference provided by Jon on NASIOC).

As additional evidence of why using fuel to suppress knock is a horribly inefficient exercise consider the following:

"...thus one can conclude - correctly - that hydrocarbons inhibit the oxidation of CO.

It is apparent that in any hydrocarbon oxidation process CO is the primary product and forms in substantial amounts. However, substantial experimental evidence indicates the oxidation of CO to CO2 comes late in the reaction scheme. The conversion to CO2 is retarded until all the original fuel and intermediate hydrocarbon fragments have been consumed."

* Source: Combustion, Third Edition, Glassman, p. 76

Performance tuning that involves fuel dumping necessitates overly advanced timing resulting in timing induced knock (and as has been experienced by others engine destruction) because the significant power release from combustion is delayed to the point where MBT is very late while waiting for the excess fuel is broken down during the extended initial stages of combustion. In upgraded turbo applications this becomes extremely apparent as the increased air flow necessitates ever higher fuel flows to maintain these supposedly safe AFRs of 11:1 and richer.

More simply consider the following - what power enhancing purpose would excess fuel serve once all the oxygen in the induction charge has been utilized in combustion? It can not and will not burn, Glassman has shown that it even interferes with the complete combustion of the fuel that is burnt. It is only useful as a coolant and most fuels make poor coolants.

As illustrated below water injection can actually help reduce maximum cylinder pressures while increasing BMEP. This is because a properly mixed AFR of 12.5:1 accompanied by water injection increases the rate of the combustion reaction exactly when it is desirable to do so during the oxidation of CO => CO2.

http://www.aquamist.co.uk/info/images/RicardoResults.gif

*Source: [i]The High-Speed Internal Combustion Engine by Sir Harry Ricardo from here http://www.carrollsupercharging.com/oldsite/gaseous/GI-01.pdf (http://www.carrollsupercharging.com/oldsite/gaseous/GI-01.pdf) (reference provided by Jon [in CT]).

Using a mixture of 50/50 water/methanol for injection will have lower specific heat and latent heat than straight water and besides having a very high 113 octane level itself, it also contributes additional fuel to the combustion process. Contrary to what their heat values would suggest some studies have even reported such a mixture can have greater knock suppression than straight water. Additionally climates that have cold winters benefit from preventing the freezing of the injection mixture.

Conclusion on the contributions of water injection:

Throughout the process water injection helps to manage heat, contributing to higher VE and suppressing engine knock. Discounting arguments that water will rob the combustion process of precious oxygen containing air. Then in the final combustion reactions it actually improves the reaction of CO => CO2 for a faster more effective release of the bulk of the energy during combustion. Discounting arguments that it slows and inhibits combustion.

Performance tuning and miscellaneous notes on water injection and mixed methanol injection:

Always keep in mind that water injection is being used to suppress engine knock and permit tuning AFR to its maximum power levels. Water in excess of the amount needed for a safe engine knock suppression margin will hurt net output. Not leaning AFR enough or leaning it too much can result in decreased power levels as well. This has been experienced by many tuners who do not have faith in water injection and have left fuel mixtures too rich.

The relationship that you should seek to manage with water injection is the ratio of water to fuel. Metered to exacting proportions as little as 3% water to fuel can replace the amount of heat absorption that fuel previously provided when leaning from 10:1 to 12:1 AFR. There is no system that can meter water in that exacting a relationship with fuel that does not utilize a full fuel injector driver, port installed nozzle jets, high flow pump(s) and a rising rate pressure regulator. At this point you are talking about stand alone engine management like a Motec and a duplication of the fuel system but for water. That being the case the best solution is to use a system that will get you as close as you can to mirroring the fuel injector flow and run at least 10% water to fuel for margin.

Some water injection users have used significantly higher water to fuel ratios (25%+). The technique usually involves increasing water flow until the engine bogs down or comes close to misfiring then pulling back a little bit, before leaning the AFR significantly and finding the MBT advance needed. These techniques take significant amounts of experience and are less compatible with most street setups.

Average street uses should try and target 10%-15% water to fuel. Aggressive street and moderate track use can pretty readily utilize as much as 25% water to fuel especially when using a mixed methanol injection system.

In general water injection and mixed methanol injection not only permits advancing timing, it is required due to the slower initial flame front (though late stage reactions are sped up) during combustion. This is contrary to many nitrous techniques so great care and skill must be employed to find the appropriate balance when trying to use both water and nitrous to make significant power gains.

When adding 5%-7% water to fuel without leaning rich fueling levels - a degree or two of advance will produce almost the same power result as without water injection (leaning slightly will increase the power output). This is good for people who have engines tuned for high octane or race fuel but on a daily basis want to use lower octane grades. This is purely an economic use of water injection - power use requires fuel and timing tuning.

The more boost you are running and the more fuel you are replacing with water injection the more dangerous it becomes to run a constant pressure / static flow water injection system. In order to prevent bogging down the engine at lower boost loads the flow of water is less and less likely to be sufficient for your full boost application in these static setups.

The state of your air/fuel mixture and timing after performance tuning for water injection or mixed methanol injection will be more than sufficient to destroy your motor if the water injection fails while under load. The responsible user will take measures to ensure adequate water is in supply and flowing during high power usage. Ideally along with a fail safe that will cut boost if a fault in the system occurs. At a minimum warning lights for water level, water pressure and water flow should be employed. Ideally triggers that close all boost solenoids in automatic response to faults would be employed by high end systems.

The entire body of information in this paper was developed relatively informally by me over the last 15 odd years through research, reading barely comprehensible scientific papers and through verbal and written discussions with others about our mutual experiences with water injection. And some of the most important additions to my knowledge have been contributed by the helpful response of people who have read and reviewed this work online. I hope it has proved a beneficial addition to your research on the subject.

That is a good article, the link I posted in post 103 above. It is useful to understand WI, but it is written with the gasoline motor in mind. The thermo is the same for the diesel, just no detonation benefit I am aware of. That might be a good invention, changing diesel fuel timing with WI.

There is a part of this article that I find disturbing, mostly because it confuses me in defining the goal of WI. Is it to evaporate a water/meth mix or not? The article almost justifies, boasts the systems lousy evaporation efficiency.

Quoting:

The injection of water into the induction charge will immediately absorb heat from the charge thereby increasing its density. Evaporation of the water at this point is unlikely or very minor. The induction charge can at a maximum reach 100% relative humidity and will stabilize at an equilibrium state that is governed by temperature of the charge exiting the turbo and the relative humidity of the ambient air. At full saturation the induction charge will have a significantly reduced temperature somewhere between the ambient temperature and the temperature of the injected water.

Aquamist promotes a low pressure (100psi) system that outputs avg 50-100 micron droplets, spraying it right onto the opposite wall of the duct, not the best way to evaporate water. So the statement may be correct, but I am confused. Are they trying NOT to evaporate until the intake valve? Because if you want to evaporate (and cool) more, simply get higher pressure behind a smaller nozzle, and point it down the length of the ductwork, presto, 10 micron fog, flash evaporation.

Unfortunately, the article speaks in terms that are too general.

I think it's important to specify exactly the application. In my case, i.e. no IC, heat from boost will evaporate the water so high pump pressure and smaller nozzle orifice isn't as critical. I don't believe you have that situation with an IC so the atomization (not sure of the difference between atomization and vaporization) of the water becomes critical and can only be accomplished with high pump pressure and smaller orifice size.

I also specifically disagree with this statement

At full saturation the induction charge will have a significantly reduced temperature somewhere between the ambient temperature and the temperature of the injected water.
He is assuming very little evaporation, with a post-CAC settup.

It is clear that temps below ambient are possible in water injection, or any evaporative cooling application for that matter. The temp of the water has almost nothing to do with the resultant heat absorption from the evaporation process, only that it must be below its BP. Even 212 degree water absorbs an enourmous amount of heat during it's state change to vapor. HUGE, as previously mentioned, 500 times the heat of the same water being heated 1 degree. You would have to use a gallon of -300F water going to 212 F (liquid), to absorb the same amount of heat in evaporating the same gallon from 212 F (liquid) to 212 (gas). (which is why we cover a pot of boiling water on the stove to save a LOT of energy boiling it, recondensing water on the lid reverses the state change and the energy consumed is negated.)

BTW this is how the energy absorbed is calculated. Although water can vaporize at 80 degrees, you calculate total energy absorbed by going from
1. 80 to 212 (using the specific heat of the liquid),
2. then adding the energy to change state at 212 (using waters latent heat of vaporization),
3. then adding, or subtracting the specific heat of the steam product as is comes to rest at it's final temperature.

This 3rd step does add heat back in to the result (when resultant charge is below 212) and must be factored.

See now why a pre-turbo fog, at high boost levels, will evaporate instantly? The outflow would otherwise be over 300 F, where water is easily evaporated without much effort.

Steam tables are a part of this, unfortunately they cost a lot of money, but the good news is that even Walmart carries the Chem E ref handbook which has them.

Forget the technical jumble, the question is, does the cooled, humidified charge have more oxygen or not? I still have a question on that and I think that was fingers question. But this is not the only question. The colder charge has more "potential" energy for combustion, not just because of additional oxygen, but because of a thermodynamic efficiency concept That I can't even grasp right now.. that has to be factored. The colder the better.

Sorry for rambling out loud, it helps to type it out. For those of you I put to sleep, be grateful you don't spend your time like me.

Spindrift,

I think you are correct. You are also fortunate, you have no CAC pressure drop to deal with, and you don't have to worry about condensation killing it's boundary efficiency.

Most of the talk has been internal.....but some mention was made of external misting and I just wanted people to think about the possibility of pissing off the track techs if they were thinking of looking at that as a method also......

Interesting stuff with all the science behind it. All i know about water meth is you make more power with it with lower EGT's but if you screw up and add a little too much you will destroy something. Too much N2O or fuel or what ever dosnt seem to have the instant grenade effect of the motor as injesting a slug of uncompressable water does.

spraying co2 on the intercooler is much more effective than spraying water on it

Newb here..please some mercy :)

Has anyone ever tried running higher concentrations of alcohol with the diesels?

I mean coming from a gasoline reference all the dyno pulls, studies, etc have yielded more power eliminating the water. And the methanol has been way more forgiving when over sprayed. Tho someone injecting a high volume would have a huge price to pay.

I'm intrigued by this thread, its the longest I have ever seen as it pertains to an injection system. You all bring up great points, hope I can add to the pot. Just need a better understanding of the ins-outs of a diesel application.

I'll state this, you cannot run a solenoid with PWM and have it survive under high pressure. Perfect example is the NOS systems that are progressive.

I was working on making a progressive controller for propane and the solenoid was the sticking point in the project. To which fuel injectors would have to been used. But fuel injectors cannot handle the high pressures.

Thx

PS.. i'm up for the challenge :D

I'll state this, you cannot run a solenoid with PWM and have it survive under high pressure. Perfect example is the NOS systems that are progressive.


PS.. i'm up for the challenge :D
Fingers??? Where are ya? Deep in the steam tables?

Yea, steam tables, more on where it has lead me when I can verify my math.

PWM:

You can run ANY solenoid with PWM and get partial opening/closing. The problem is the duty cycle of the component. They build up an impedence that generates a lot of heat in some applications. The driver AND the solenoid coil have to be up to the load. After all, PWM is nothing more than opening and closeing the valve rapidly, generating a fair amount of current. Another issue is the valve seat. If the frequency of the PWM is not right, the valve will chatter against the seat, wearing it out fairly fast. Ideally, you want the needle, gate, or whatever to float between the limits. Adding mass to the plunger helps dampen this, but slows the response time too.

For testing, you can almost get away with murder. Long term durability requires more carefull matching of the components.

The pressure is not the problem, otherwise our 28,000 PSI injectors would be toast instantly. Point me at a failed progressive system. Probably chattered the piss out of the valve, provided it was rated for the pressure in the first place. Dealing with the feedback from the solenoid coil can cause headaches too.

Now to really get a reliable system, you should get coils that have been wound specially to work well with PWM drivers. But that costs money :)

Razor, welcome to this crazy place. Careful, it's bad for the bank account.

Now to really get a reliable system, you should get coils that have been wound specially to work well with PWM drivers. But that costs money :)
Ahhhh... thats the boundary I hit. All the progressive type solenoids in the world are for industrial automation.. the BIG cash register Cha Ching bell hits when looking for those. Hell 500.00 for a solenoid is not uncommon. Then they're not linear so the drive has to be "curved" to make the solenoid linear.. its a mess to get rite, expensive, etc..

Razor,

If you give me some details, I might be able to tell you how to clean it up. Schematic of the controller would be good too. Also, what was the failure condition of the Solenoid, Mechanical or coil?

Time to get going on this. When used for cooling, a lot of DIY systems waste a lot of water, misting during overlapping periods where the motor is not benefitting. Pump will be modulated with a MAF or MAP input controller. A cockpit switch chooses Towing mode or Performance mode.

1. Towing mode-water miser. :) An intake mounted adjustable temp switch, with only a few degrees of hysteresis, inhibits operation under threshhold CAC temps, . When above these temps, modulation occurs with pump PWM method, so misting stops the instant that the D-max is unloaded. Low mist flow is emphasized and flow automatically increases with workload (MAP). Series connections insure "AND" logic. Both, temp and charge air flow conditions must be satisfied before pump will energize. Injection takes place post-CAC, after the temp switch. Used this way, 25-75% less water will be used vs straight MAP modulation, by virtue of not using WI when the CAC is doing a sufficient job of cooling charge, cold days, rain, straight-level highway etc.

2. Performance mode-full system modulation. :ro) When switched on, in addition to 1. above : A separately enabled manifold, spraying pre-turbo, will augment turbo performance. Will use an adjustable pressure switch in the turbo inlet or post-turbo to solenoid activate mist pre-turbo (mist manifold #2). The PWM continues to modulate both mist manifolds, with highest boost consuming the most water/meth solution. Temperature requirements would still apply, while this may be annoying to some, you need some way to keep the system dead when ambient temps are too cold anyway.

I've thought this through but I could be missing something. comments?

Razor, I read your posts on TurboBuick, welcome to this board.

The straight methanol will speed up the combustion too much. Water used to reduce concentration of methanol, slow combustion, and to add cooling. Each application will be different as to how much methanol can be tolerated depending on injection timing.

Would it be possible to use the voltage from an EGT probe as input to your progressive controller?? I forget what the input voltage range is for a signal.

Donald McMullin

Almost all voltage based sensors on the truck are 0-5 volts. So yes, you can use the voltage from the EGT as input.

Will use the Boost sensor.

Julio, I just now put 2 and 2 together. I talked to you yesterday.

You will have to tap the RPMs too to calculate Mass Air Flow. That is a PWM signal. One option is to use RPM as a base line PWM and amplify it with the Boost pressure. But that might not work well with the pump.

I guess. Realistically though, I am probably going to use an off-the-shelf controller that can handle a 15 amp load with minimal voltage drop. I just don't have the patience to re-invent one (nor the talent). The algorithm you are taliking about would be difficult to do nail down.

Let's see, we are wanting to inject a constant proportion, mass of solution, to mass of air (a diesel is an air pump). As boost pressure doubles, mass doubles. As RPM doubles, mass in chamber doubles (or close to it). To gauge fluid injected, you'd want to multiply RPM times Pressure, and have that multiple, linearly meter injection fluid.

Sound right? What would you use for RPM signal?

If your primary concern is lower exh temp and more power, wouldn't it be best to have the water go into the cylinder as droplets rather than dissolved in the air?

If the water goes gaseous in the intake tract, it reduces the available air. If it goes gaseous in the cylinder on the compression stroke, it absorbs heat and changes it into pressure raising the cylinder pressure greatly. Essentially you are using more of the heat you generate to make pressure on the piston. Ideally, you don't even want heat, just down force on the piston. Since the only way we know how to do that is by using temperature to expand air, water mist (not gaseous) expands way more than air does. You would get the benefit of reduced EGT's yet still make more power when over fueled.

Patrick,

Were you in the Air Force?

Patrick,

Were you in the Air Force?

Nope.

I just have seen alot of various stuff in my line of work.

Sorry, I thought you might have been someone I knew. To reply to your questions, conventionally, you are describing the concepts of how water/alc have been used in the past. I am just going to toy around with it.

As for Oxygen displacement, everybody's concern, steam creation above the BP is different, volume wise, than ambient evaporation. I better go break out a chemistry book before I put my foot in it any deeper. The other thing I want to test is the ability to increase turbo efficiency at the higher boost levels (still searching for our map diagram, anyone have one?).

Water is not the only consideration also, the meth evaporates 4x faster, so creating the meth rich air charge is part of this. Unfortunately, it has only half the Latent heat of Vaporization. If all we are doing is displacing O2, then we are spinning our wheels. When I find the moldy text, I'll find where moderate injection at lower temps puts the meth molecules between the air, instead of in-place of it.

If you have done this all already, you are way ahead of me.

There is Sooooo much going on here, and everyone is correct, at least in theory.

Injecting pre turbo will increase the density of the Air charge. The increase in charge density is greater than the displacemnet of O2. So there is a net gain. However the diplacement also slows the burn in the chamber. Good or bad I don't know. The amount of injection must not be greater than the post CAC saturation point or the water will condense in the CAC and cause trouble. The mist should evaporate well due to the turbulence induced by the turbo. This is not the case post CAC.

Water injected post CAC will mostly enter the chamber still in droplets. There is some cooling, but it is not significant. Temp sensors down stream of injection suffer from a wet bulb effect as water evaporates off thier surface giving false readings of how "cool" the charge has gotten. Without significant mixing, the evaporation rate is not fast enough. The droplet size making it to the chamber seems to be the same regardless of injection rate. However, as McRat said, that is a good thing. The water droplets absorb heat and generate vapor/pressure in the chamber. The droplets do not displace nearly as much O2 as evaporated water per injection rate, but the charge is not as dense either.

Which is better? I don't know for sure. My math sucks. Indications are that the pre-turbo injection is more efficient but limited by the amount of water that can be evaporated. I don't have handle on how much, if any, reduction will be seen in EGTs. That calc is just outside of my ability. IF any of the turbine case studies are any help, the engine can produce and additional 5% or more power, but again, it isn't clear the EGT's will come down.

...the case for water only, nicely said. Water/meth: a different story somewhat. The neatest thing about multiple immiscible solvents is that both will evaporate at the same rate, despite the existance of the other. Fully saturated air (100% humidity) has no affect on the further evaporation of meth, or isopropyl, or acetone, etc, restatement of Daulton's laws I recall.. So even when the charge is cooled as much as you can with water, enter another compound, and more gas cooling (albeit at reduced temperature). If only there was enough o2 to go around and combust it all.

Because of it's affinity to evaporate, volatility, methanol is the product of choice for power hungry hobbyists who have relatively innefficient, cheaper misting settups. Per gram, it cools twice as fast as water (although water has higher cooling value) while creating a vapor fuel. It is more shortlived in liquid state.

If this were strictly, how to create most power and EGT reduction, I'd evaporate meth across the turbo, and then inject water post-CAC. I have a feeling it would come apart. Wish I had some testbeds and a crew to test the theory.

Still learning.

To gauge fluid injected, you'd want to multiply RPM times Pressure, and have that multiple, linearly meter injection fluid.

Sound right? What would you use for RPM signal?
Calling Fingers. How have you put any thought into this? There is one or 2 "mappers" out there already for this.

The RPM signal from the crank is PWM at 12 volts. The ECM puts out a clean and corrected PWM tach signal at 5. Either can be highjacked/tapped. The Boost pressure signal is linear voltage 5 volt.

What input into the motor driver do you need? Voltage or PWM?

I'm all "thumbs", fingers when it comes to electricity.

I was wondering if you agreed with my algorithm reasoning.

"What input into the motor driver do you need? Voltage or PWM?"

not sure what you are asking. Let's say we are going to make a controller to drive a shurflo diaphram pump. We need a 12 volt PWM signal (output) for this from the controller, right?

There are off the shelf drivers to generate the PWM at the rating you need for the pump. Better/cheaper to use them for the grunt work. They all want some sort of control input. Usually a reference voltage. The custom low power control circuit you need will convert the Tach PWM to a voltage and multiply that with the boost. Op-amp, some caps, resistors and a couple of transistors. Radio shack cookbook stuff.

Any progress on anything??? MasterP2?? Fingers???

Hate to see a good thread go away.

Why would you pulse the motor instead of pulsing a solenoid and leave the motor running?

McRat,

First let me say, as usual, I am not an expert on how this is best done. If you have some good ideas, don't stay in the background. Of everyone here, I am probably least qualified.

"pulsing". Not sure if you are referring to the built-in pressure switch on the pump? I am not going to use one. So pulsing should not be an issue to vehicle performance.

I have decided to PWM the pump largely due to conventionality, and also due to what I think is a good strategy to keep the motor from burning up. The pump will operate in a high ambient T environment, 140+ at times. Most pumps I have looked at have a thermal switch that will disable the pump after it heats up high enough, some as low as 175. I won't disable the thermal protection with methanol running through it.

So higher peak pressures with better motor longevity is why.

Continuously operating the motor at the high pressures I would like to design, would quickly disable it. With DC motor PWM, I can overwork it for short periods at much higher pressures, with minimal heatup consequences. Also can run it for towing at lower pressures, for very extended periods if desired.


Yes, No? This is the time to illuminate me, it's still on the drawing board.

If someone could point out a good schematic source on the ECM wiring harness, a way to decipher what each wires origin is, that would be appreciated. i think I have seen a source for this.

Look in your SI manual. The info is in the connector descriptions.

Didn't think of that, thanks. My SI is on CD, and I don't really like it very much. I probably don't know how to use it very well. Thanks Fingers.

I did find a wealth od information here:

www.gmupfitter.com

I love that site now. very pictorial.

OK, found a boost and a MAF signal to play with. Now I need a tach signal. Can't use spark.

The RPM signal from the crank is PWM at 12 volts. The ECM puts out a clean and corrected PWM tach signal at 5.
What input into the motor driver do you need? Voltage or PWM?PWM. Here is a synopsis of what I see on the diagrams, LLY only:

It appears that there are 3 ECM connectors. I don't know if all have input and output pins, or which of the three is ECM output, my guess is that each connector has input and output signals.

C-3, (grey connector) has pin 37 (white wire) as engine speed signal. Pin 18 (PPL) is crank voltage, I assume the 12 V you speak of.

C-2. (black) has pin 63 (Lt Blu) as engine speed also. Pin 23 (lt grn) is turbocharger boost sensor signal.

C-1 (Blue) has pin 13 (yellow) as MAF sensor

here is the LLY MAP circuit. Note the sensor part number, and it is 5V. But if I interpret this correctly J2-30 is the variable output, or not??

I don't get why the sensor has three connections. Fingers, educate me buddy!

Also, still trying to de3cipher an RPM 5V signal.

here is the LLY MAP circuit. Note the sensor part number, and it is 5V. But if I interpret this correctly J2-30 is the variable output, or not??

I don't get why the sensor has three connections. Fingers, educate me buddy!

Also, still trying to de3cipher an RPM 5V signal.

The variable voltage is at J2-23. The little arrow is the "Tap" on the pot. The tap essentiallly splits the pot into two resistors. Ohm's law applies.

If you tap any of these sensors, you need to make sure your tap does not change the voltage "seen" by the ECM. That is, you need to provide isolation.

...and J2-30 is the equivalent of gnd? Thanks fingers

I find no ecm circuit that has a 5V ref RPM or Tach signal. May have to abandon that. The electrical schematics, LLY and LB7, are

here (http://www.gmupfitter.com/publicat/2004_BB/2003_Beyond_LD_Electric_CK.pdf)

All tach signals are PWM.

Maybe, but I can't find a 5v ref PWM for tach. I found the crank RPM, I thinks it's 12v like you said. Need one that is 5v. Is it possible there is none?

Are you saying that all PWM is on a 5v standard?

I don't know if this helps, but tach is circuit 121. I want to say its in connector 1 on LLY ECMs (may be the 3rd one, one is wait to start and I know they're in connectors 1 & 3, but don't remember which is which right now). The description is in volume 3, in the 39xxx section. Not sure what the voltage is though.

Yup, that's the one I've been lookig at. I'll check the voltage, but it doesn't have a 5v ref signal, so I think it is 12v.

Yup, that's the one I've been lookig at. I'll check the voltage, but it doesn't have a 5v ref signal, so I think it is 12v.
It is PWM. Two pulses per 100 revs if I read that correctly.

Have been playing with a couple of different misting ideas "out of the box" to improve evaporation efficiency for the power hungry.

I also am working closely with Julio, a designer of one of the best controllers in the WI market. We are collaborating to produce a system that is temperature limited, thereby greatly reducing the water-uptake during periods of non-heatquenched operation, for towing specifically. While it is still developing, it will likely still be modulated via MAP or boost, but inhibited under cold intake conditions, the final temperature TBD. If anyone has a suggestion what temp the intake should not exceed, feel free to suggest. That is the challenge right now, to determine the intake temp at which water should flow for the towing mode, the performance mode will bypass this limit entirely.

BTW, this temp limiting idea also protects the user from using it in conditions that are just too cold to be using WI, induction ice can/will occur with some conditions though not likely a threat. The bigger threat is providing TOO much performance, lifting heads, which a real cold saturated alcohol air mixture can concievably do.

So anyway the ball is still rollin.

Julio is great guy and should be able to take care of any needs the DMAX should need. Keep us posted.