Steam injection pre turbo
 

Why would steam not show the same characteristics as a very fine mist of water when injected pre turbo? My home steamer's mist is not hot further than a few inches from the nozzles- ie it's cool after three inches. I would think with a inverter and a 115 amp alt I could power the steamer and utilize it pre turbo. Thoughts?
I posted the same ? over at WI forum.

You would not gain anywhere near as much power as it takes to make the steam.

The power in water injection comes from the water to steam expansion rate = 1:1,600. Also, the transition from liquid to gas takes (a little) energy. I would think that a vapor mist would work better than steam for this reason. It could not contain any minerals though which could be abrasive.

Incorrect, pure water injection produces no (zero) hp increase. Alcohol (Methanol) must be mixed with the water before there will be any power gain.

Incorrect again, evaporating water takes lots of energy. Thats why it cools the air.

Although I've never had water injection on a diesel, we used it successfully on gas engines w/o methanol and got substantial power gains. I'm pretty sure that it will do the same on a diesel.

water will make the charge air colder, therefore denser. On a gasser, it will allow you to dump a ton of fuel in and it will also allow you to run higher compression ratio without pre-ignition. Diesels do not have this problem, so it really does nothing more than cool the charge air. If you were to dump a ton of fuel into the mix (which we can't do with the stock IP), it might help to keep temps down. Otherwise, as Forced said, there seems like little benefit... However, water injection combined with propane injection might prove useful...

GB is right. Denser air on a gas engine means more air and fuel flow into the cylinders.

Denser air on these mechanical diesels does nothing but help it run cooler. I have used water injection and the difference between no injection and pure water is 0.3HP and 0lb/ft of torque, easily within the error range of the dyno. View it HERE.

Using a 50/50 (by weight) methanol mix at 300cc/min added 3.2hp and boosted torque in the upper RPM range.

It would help the cylinders run cooler- and I think perhaps I'd get a bit less smoke out the tail pipe, which are two good things in my view. The 110 volt steamer (600watts) would take little power from the engine, as it would tax the battery and alt a bit, but certainly not much. WI helps keep the cylinders free of carbon build up also IIRC. There's three things. My real question is the effectiveness of steam. Yes, the cooling of the intake air comes from the water to gas transformation; and thus the conventional wisdom says you cannot get that energy back to cool the air. However, the steam is really no longer steam less than 6 inches from the nozzle, so I fail to see how this applies. Try it- home steamers are just water soakers 4-6 inches from the point of exit. Pre turbo amounts of WI are much less than the post turbo amounts needed for the same effects also. I view it as an overall safety feature if you are running more than stock amounts of fuel, air, and other combustion gases- propane, methanol or alcohol.

Water injection = good if the cylinder temps are getting out of control.

Last week we dynoed 924 HP with Diesel and 949 with a water injection system using pure water. This was a Cummins, not a MBZ though. Not a huge increase, but the system is to save the engine, not add power.

The little MBZ with moderate fueliong increases may see a few ponnies if your lucky, but it may be so small you would hardly notice.:confused:

Once you get one cranked up to 500 or so....then the water may add a few more.

We were only getting about 4HP from water, but tweaked it a bit for 25 more!

:)

Great.... What is needed here is to address the question at hand. If you have information of what you are doing now and how it relates to what I've or others have asked, let's hear it.

My question is if you are willing to go that far, why not get a good pump (~$50) a nozzle ($10) and do it right?

A person could use the heat from the exhaust pipe after the turbo to create steam and it would draw no power from the engine.

You are missing the point. The water is used to cool the intake air. If it is already hot steam there will be no benefit since the water can't absorb heat from the air or evaporate.

I have not found a $60 system that "does it right" for pre turbo injection. Post turbo is complex- you have to have the proper installation at a suitable post turbo/post IC site. I don't have such a site unless it's gonna be right at the cylinder entrance- which means I'll have five nozzles. Your previous system may have had this issue. It also means I have to inject much more water- over 500 cc according to many, including your estimates. Reading thru many threads over at WI show the complexities that accompany post turbo, and even pre turbo.
The major issue with pre turbo is the water drop size- causing impeller damage. Steam condenses if it has the distance/time and will still be small enough water droplets that it should not cause this damage. That's the theory, and until it's hashed out, the subject will not be closed or fully explored.

Does steam stay in gaseous form without further heating? When it enters the cooler realm of ambient air it starts the transformation to liquid. Water in liquid or gas form will clean build up in it's path, and that is a benefit itself. Obviously using heat already made by the engine sounds like a win/win, however I believe both you and I think at this point it may not be worth the time to design, fabricate and install a system based on this.