Pre-Turbo Water Meth
 

Pre-turbo water meth

By our very own Chris Foogle

yep, here's the deal.....the compounds are only days from going in, but I wanted to try chemical intercooling before I went to the extreme of plumbing in another air to air.

This shows how far the nozzle carrier and feed pipe extend into the inlet tube

http://img411.imageshack.us/img411/5881/t1li8.jpg

here's the two intake horn nozzles....an 865 cc/min and a 520 cc/min (@ 200 psi). Because I have the intake nozzles staged later than the pre-turbo nozzle, I have also placed a solenoid valve in line which is controlled by a Hobbs switch located in the intake manifold, which is set at 30 psi to turn on the intake nozzles.

http://img119.imageshack.us/img119/2732/t2nk9.jpg

This shows where I mounted the pump...behind the PDC on the fender, and the resevoir.

http://img206.imageshack.us/img206/1282/t3ey9.jpg

here's the hobbs pressure switch under the air horn that enables the air horn nozzles.
http://img502.imageshack.us/img502/7130/t4tw4.jpg
http://img502.imageshack.us/img502/7...c79f8c67ba.jpg

here's the pre-turbo assembly. Note another pressure switch that brings the pre-turbo nozzle on at 20 psi, another solenoid valve to keep it isolated, and cut down on afterbleed

http://img404.imageshack.us/img404/5144/t5kv1.jpg


here's the pre-turbo nozzle in action. It is a furnace nozzle rated at 5.5 gph, though at 220 psi closer to 8 gph (500 cc/min). It is a hollow cone to not flood the compressor wheel nut, and an 45* angle to stay close to the center of the wheel. The standard spec of the nozzle is a 5.50/45*A. 5.50 being 5.5 gph at 100 psi, 45* being the discharge angle, and "A" denoting the cone type...hollow in this case

http://img117.imageshack.us/img117/1230/t6an2.jpg

here's a close up of the same picture above. Note the narrow angle of the spray pattern keeps all the water towards the center of the wheel, negating any tip erosion. Note as well how the hollow cone of this nozzle nicely works around the nut, even though it is very close to the wheel. This nozzle sprays at 6 microns @100 psi, which is below the size that supposedly starts to cause tip and leading edge erosion. Time will tell, but wheels are cheap compared to the awesome advantages of spraying, especially in compounds, as I intend to finish in the next few weeks, to act as an intercooler.

http://img209.imageshack.us/img209/9353/t7xu7.jpg

so there you have it....now for the results. I really wish I had a dual channel IAC gauge, maybe in the near future, but for now, the seat of the pants as well as the boost and pyrometer tell enough of the tale to know the results. In high gear at a sustained 20 psi, and upon activation of the first stage (pre-turbo), boost increased to 26 psi without any accelerator change...the compressor section definitely became more efficient, acting as a larger compressor. As EGT's aren't high (800*) at this point, the turbo is in it's highest efficiency state, and the aftercooler is fully capable of cooling the current intake charge temps, there is no other aspect that can explain the increase in manifold pressure other than the injection pre-turbo obviously made a big difference in the compressor section of the turbo. Now under full acceleration at the 35 psi ceiling I have the turbo set at, my net manifold pressure climbed to 43 psi with the full system in operation, and egt's dropped by about 300*. I could never use more than about 2/3 throttle in 5th, or temps would pin the gauge. With the injection on, I max out at 1400*....still a bit high, but the compounds will take care of that.

So there you have it. Come to your own conclusions, but I believe pre-turbo injection just might be a way to increase a small compressor's efficiency past any other means available. And the benefit of pre-turbo injection will be even more invaluable in compounds to cool the air between stages without having to fabricate an air to air intercooler. By hitting the secondary with water, the end heat result will be well within the aftercooler's ability to efficiently casue a reduction in charge air temp. Follow that up with some post cooler injection and intake temps can be way down and consequently air mass very high. This will enable us to keep the compressor(s) in their peak efficiency range, and not push them into the upper reaches of their map, especially the secondary. I will know more when I can swing an IAT gauge as well as incorporate these theories into my compounds. Until then let the opinions and debate ensue...........

Chris

Wow you have been busy, looks like a good setup for pulling and dragging to keep temps down with out having to spend a lot of money on turbo upgrades.

Actually water/meth is only reliable up to about 700hp. Anything over that and it causes problems due to the IAC being supersonic and the water no longer having the cooling properties because it is changing state too quickly.

Kevin, is that yours?

no.............its Chris Foogle's....CumminsExpress :5:

Chris,

I have been advocating pre-c wmi for some time now.

Can you rationally explain what causes the boost increases?

How much pressure drop do you speculate from the added nozzle apparatus?

Well Kevin Dug this up from the grave....I ran the system for quite a while with good results. At the time my goal was to make a stock compressor act like a bigger one, especially when introduced higher intake pressures and temperatures from a primary feeding it. I had to take it off due a nozzle holder failure from some very rough off-road action. I stump-holed the truck and the weight of the nozzle/holder broke the feedpipe that it was mounted from. I never got around to re-designing a replacemnt, even though i meant to. There is....and still is...a lot of controversy about introducing liquid into a compressor's inlet tract and wheel. Some have had catastrophic results, and I suspect mostly due to inadequate atomization from poor pressure or nozzle, or after injection dribbling. Both scenarios will grenade a wheel in fairly short order. I took a lot of time researching nozzles and pressures. Quite amazingly, furnace nozzles offer a sub 10 micron droplet size at 100 psi (IIRC), a variety of cone angles, and solid, hollow, and semi-solid spray paterns. Nozzle placement as well as proper plumbing to prevent dribbling is paramount. I hit the nozzle with 200 psi, chose a vary narrow, hollow spray angle to keep the pattern radially close to the wheel hub and away from the tips, but not cover the shaft and nut with liquid to cause pooling and the "BB" effect. I ran the system for about 10,000 miles and never saw any visible erosion or damage. This is not to say, however, that even at 10 microns or less, dusting is a variable that HAD to have been happening, and it's a case of discretion as to when and whether to replace the wheel pro-actively or not. I would assume, that under normal duty cycles associated with only high boost activation, whether street or track, that the turbocharger would probably see it's service interval sooner than wheel deterioration would occur. But, there are so may variables that play into the scenario, that it's impossible for one shoe to fit everyone. I will say, however, that the more attention you give to detail and set-up, the better and safer results you're going to get.

I also never gave any results after installing the twins, which was the whole reason fro the idea anyway...to negate compression losses to heat due to a high secondary inlet temp from primary compression effects. I can't find my hard numbers presently, but I'll rely on memory to get as close I can recall. At peak boost, the primary was delivering 38 psi to the secondary at +/- 380*...yes the primary was overworking and making some hot air! without pre-compressor injection, the resultant post secondary pressure was 71 psi and +/- 450*. This is a scary high number isn't it? But, as aftercoolers become more efficient the hotter the inlet air is, it was still able to knock down the IAC to just over 220*. Mind you, this is PEAK numbers...full throttle, full fuel, peak boost and at 4000 rpm...and a highly modified secondary turbine. Now with the pre-compressor meth on, just as with the single charger testing, a rise in pressure was observed, though not as drastic...maybe 4 or 5 psi. What DID change however, is secondary outlet temp. IIRC, oulet temps were reduced by 100*, which may not sound like much, but in the world of thermal pressure dynamics, makes a huge difference in air MASS. I wish I could have spent the time and fabbed up a MAF and MAP sensor(s) that could handle the airflow to plot the air numbers, I think the results would have been remarkable. Since Kevin re-kindled this topic, I feel motivated to try it again and take the testing farther. After losing my access to lathes and mills, however, due to moving, the fabwork may be a tad more difficult :) For those interested, Aquamist was doing some fairly in depth R&D on the subject a few years ago, though I have not kept up with it since then. Might be worth checking out.

Killerbee....Having no real education or training in thermal dynamics I can only surmise my opinion from ration and mechanical logic. Since cooling the air charge should theoretically condense it in terms of mass, the result should actually be a drop in MAP, not an increase as my results, and even aftermarket mfgrs results show. So I adopt this theory. Injecting water in an airstream with the environment such as an intake tract where temps are potentially, and usually higher than it's boiling point at an ambient pressure, do we assume that the rise in pressure is due to the expansion property of the liquid turning to a gas aka steam? And if so, when we introduce the pressure influence on the water's liquid to gas state...what then? I don't know. The droplet size might predicate an elevated evaporation rate on a grand scale regardless of the pressure exerted on it. I would really like to know for sure as well. As the results don't jive with the properties that are occuring, but no one has questioned it and investigated! I can say, however, that the pressure increases could be as simple as more combustion energy acting on the turbocharger and creating more boost. The secondary gate setting predetermines it's rpm and consequently boost, but the primary is non-gated, and could actually be making more boost right off. I, unfortunately don't have any data on primary compressor output...either I didn't track it, or have forgotten it!! As far as the pressure drop from the nozzle, do you mean the injection pressure output of the pump from an added nozzle? If so, when I first fired the system, the large nozzles at the air horn in conjuction with a large nozzle at the secondary turbo caused the pressure to drop to less than 130 psi. While this is still in the operating range of all three nozzles, I was worried that spray pattern might be compromised. I put in a set of "325's" in the air horn, which brought final flow pressure up to 175 or so...again all from memory.

Anyone else interested in the subject? Damn long post again.....sry.

Chris

keep up the good work Chris....we love it man and hopefully we all can learn by yer experiments :U:

LOL...experiments or parts destruction whichever sounds politically coorect at the time. My wife has a view for sure. She is still wondering why I changed out that secondary for some marine John Deere laggy bastard. She's just used to her '01 with it's HY35. You still have to DRIVE a fueled 12valve. Anyway...thanks for the post Kevin...did you get that off of CS or CF?

Chris

from the thermodynamics and fluids side of things i would think that adding the water pre-turbo would cause the water to heat up along with the air during the compression of the air in the turbo. the water would retain the heat more so then the volume of air. although it would help in the inter cooler to increase the heat transfer from the volume of air to the inter cooler. have you guys thought about water injection post turbo and pre inter cooler? just thinking about it engineering wise.

I'll shed my thought on your experience, Chris, specifically the map increase. I have to make the assumption that your map sensor is located at or near the intake plenum, and also that you have a wastegated turbo. Sorry that I am not more familiar with the ctd and dodge mechanics.

The job of the wastegate is to take a pressure signal, from the compressor discharge, and use it to bypass exhaust flow at a given COP, compressor outlet pressure. My suspicion is that the water is changing the dynamic of the wastegate.

Take this for what it is worth. If you have ever seen 10 micron atomization, it looks white, and the droplets just barely descend in a free air stream. Fog is 10 um. From the closeup pic (very nice photography) I would estimate your sauder mean diameter to be in the 60-80 or above category. It is the same challenge everyone fights. But your method does not require attention to this detail. By centermass aiming, the drops are hitting at low velocity, without the threat of impingement damage, obviously you have thought this out in advance. The mounting looks scary to me. That environent is full of mechanical stress challenges that i do not pretend to fully understand.

Yes, the mounting was an attempt to not disturb the airflow too much. The injector body and nozzle are of the same diameter as the hub of the wheel, and the standpipe does not enter the airstream until the 90* bend at the injector holder. The solenoid valve is bracketed.....however, as said earlier, the tube broke on the outside of the compressor from vibration and some rough bouncing at one point. The tubing is heavy wall chrome plated brass...but brittle is brittle and that's where it broke. This is the reason I wanted to build a new mount using a 3 camered spoke ring and a smaller nozzle/carrier. I just need to figure out the best way to deliver fluid to the nozzle without creating too much turbulence with a water line. I would like to run it through the 3 spokes that would be hollow and feed it from the outside. We'll see, I want to revisit this project though and take it farther. Who's making some top of the line nozzles that will provide a vary narrow and hollow spray pattern yet not be too intrusive??

Chris

http://www.thedieselgarage.com/forum...ad.php?t=20617

We are on the same page. Look near the end of this thread for the mount you described. I still have not prototyped it, but some day.

Oh, ignore the morons on that thread. We know better.

Keep the personal attack out of this please. The vast majority of those posting in the thread are certainly not moron's and have very valid points especially when your talking about an unproven "theory". :c:

Is this thread discussing an unproven theory? If so, somebody should tell Chris.

Obviously the points of the "vast majority" have been invalidated here. Thanks for pointing that out.

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I was curious if you knew or speculated how much added resistance the apparatus added to the high speed air stream. With air likely exceeding 300 mph, it is kinda sorta important to compressor efficiency maps.

Yes...it is an unproven theory or else there wouldnt be anymore need to debate the issue. Chris isnt lobbing personal attacks but debating the topic of discussion. No more personal attacks.

The vast majority still believe in evolution. Once again an unproven theory. Get on with the topic of discussion without personal attacks or negative attitude. Thanks for your support.

okay, a little background on the project is in order to clarify it. When I was playing with this idea, I was in the process of fabbing for the compound turbo install. Just a few years ago, secondary turbo selection left for a choice of streetability, or high horsepower. There was a large gap between the two. Most used their factory HX35 to maintain off idle performance at a sacrifice of reducing top end HP potential, as well as toning quite high drive pressures and CA temps. Of the few turbos available boasting the best of both worlds, the average guy, or at least me, had a hard time justifying the $2K price tag. After much number crunching, I realized a smallish secondary turbo could be made to act as if it had a larger compressor by 1) reducing inlet air temps, and 2) removing heat during secondary compression resulting a denser air MASS outlet. In my compounds, secondary inlet air temps (primary turbo outlet temps) lived in the 350-400 degree range. Anyone that plays with numbers knows what effect these kind of temps make on a compressor trying to compress a second stage. For that matter, how ANY turbo would react with those kinds of temps. Intercooling was sought to bring temps down, so that the secondary could become more efficient. In trade for a second CAC, all the maze of plumbing, and sheer space requirements, I opted to duplicate the effect with secondary pre-turbo WI. After all, the desired effect would only be a variable for a small percentage of engine hour time, so why install an elaborate air to air or air to water cooler for such a small duty cycle. If it was a track only vehicle...maybe...but not for the family taxi and grocery getter street rod.

While I built and tested components prior to actually installing the compounds, the R&D was really focused on them. The theory was that during second stage compression an injectable "mist" would negate the effects of high inlet temps, as well as absorb a degree of secondary compression heat. Proof? I had none. I needed to install a MAF sensor capable of handling the air flow conditions...ie high MAP and high velocity. That is where I left off. The results at the time I slowed progress showed no impingement effects on the secondary compressor wheel after thousands of miles at a rough 30% WI duty cycle, a lower CA temp at the engine all other variables constant, and a felt difference in the ol' butt meter. These days, better turbos are available, and at a slightly lower cost, but the variable still remains.....secondary living conditions are the same, so while we may be able to make the secondary more efficient and drivable with a new fancy turbo, why not improve on the conditions under which it operates?

I'll admit, I jumped on to the bigger is better bandwagon, and swapped the HX35 for a larger BW S3A. While top end is blistering, and drive pressures are optimum for 80 or so pounds of MAP, the low end has suffered. I didn't spend the bucks on the expensive S300 variants, I simply had this turbo due to a John Deere in frame we did on a commercial boat. The turbo had lots of life left, and the rest is history. I want to now go back to a smaller secondary to regain some street manners, and I'll work out how to get the top end I want as well.

Anyway, there you have it.

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After reading the entire 10 pages of that thread I see our motive is the same, though our goal just a little different. In layman's terms, I desire to make my secondary compressor act as if it were by itself, without the negative influences delivered by the primary, all the while utilizing 3x the ambient pressure available by having the primary compressor upstream. dauntimng task maybe, unattainable, I don't think so. Now I know it is lofty to think we can deliver cool crisp 70* air to the secondary, and I don't aspire to those conditions, but anything we can do efficiently to lower the current 400* would drastically increase the efficiency of the secondary, and allow us to run a significantly smaller secondary compressor. A smaller secondary would lend itself well to better off idle response due to less rotational energy demands. The unforeseen obstacle not withstanding is still maintaining adequate inlet diameter so as not to bottle neck the intake tract too much.

Back to the WI in itself. Why not do away with DC water pumps that are stalled at 200 psi, made of plastic, and prone to failure? Why not a belt driven, clutch operated 3 stage water pump similar to those used in pressure washers? At 4 digit pressures, a smallish flow furnace nozzle could be used due to the vast angle and cone types available to achieve high flow rates could they not? And at a very small droplet size? I don't believe parasitic HP loss would be much of a variable, they are driven by fairly small gasoline power plants and even electric motors.

I had to post to see your images of the nozzle mount, but after doing so realize this is exactly the mount in my mind's eye. Now if the same frame used to mount the nozzle could be made to internally carry the liquid, I think we'd be on to something!

i think its a great idea, hopefully one day ill have th emoney to do a nice setup like that on my VE truck.