Warm Air Intake With Steam

[cRiPpLe_rOoStEr]

Originally Posted by teoman

I suppose that the vapor takes up some volume. In our calculations we assumed that the vapor dumps its energy to the air transforming in to water droplets.

The air might be too cold in order to condense the steam back into water droplets. Anyway, how are you going to deal with the vaporizing of the LPG? Are you still going to keep the conventional heat-exchanger setup?

[teoman]

Wouldnt cold air condense the steam faster?

I do not intend on touching the standard lpg setup(it is heated with engine coolant and injected as a gas).

[teoman]

I found another interesting paper.
https://www.researchgate.net/publica...sooctane_fuels





It seems that between 80 and 90 degs is the sweet spot for minimum fuel consumption.

Still no idea what addition of water will do to this.

Thsi has started to appear more and more logical to me. I believe that the method I propose is an effective mean of adding a precise amount of heat to the intake. (I still need a sensor to measure steam temperature, and some data logging so that i can predict what will happen as there will be a bit of delay between steam water injection and steam generation, this delay will also change the steam temperature.)

[LittleBlackDuck]

One potentially fatal flaw - unless you keep all of the parts including the injector above boiling point the steam will condense into water...

Simon

[teoman]

Simon,

I do believe that i was not able to describe my (so far theoretical setup properly). English is not my mother tongue so that may be the cause of the problem.

- I have a copper pipe wrapped around the exhaust which heats up.
- I have an injector on one side, the injector is never heated and it has a heat-break (silicone tubing) to prevent that.
- The other side of the copper pipe is connected to the intake by hose (after MAF).

The injector shoots the water out which arrives at the pipe. As it evaporates, it expands. But it cannot escape by the route which it came from, it is blocked by the injector. So the only way to go is travel the copper pipe, then the hose in to the manifold.

My objective going this route, is to be able to control the intake air temperature precisely, keep it at an exact temperature range, instead of relying on it to suck up some unknown air temperature near the exhaust manifold.

In all of my calculations, i assumed that the steam dumps ALL of its phase change energy to the air, raising the air temperature. The steam itself condenses in to very fine water droplets.

Come to think of it, if this does not happen, it means that I have goofed up and the air is at 100deg C and cannot suck any more heat from the steam. The above paper shows that i start to get a BSFC penalty if I move away from the 80-90 deg C sweet spot.

But you and the others are right, i may have to do something to prevent water accumulation in the system. Shutting it down several minutes before i reach my destination to let the air dry the water or increase the insulation or some such mechanism.

[teoman]

I had the idea that the EGR valve might be a good place to inject the steam. Then i started researching my intake manifold.

Here is a picture of it.


The pipe with the garden hose attached is the EGR hose.




The intake manifold looks like a fancy one.

(Not my pictures)


It does not look like the egr gas reaches all of the cylinders equally.

[gumby79]

Useing a "dry boiling pot" as you describe solves the question of ,what to do about excessive head pressure/ steem production when demand is less than production. Nice work . I like.
Dreem big chisel down to reality

[t vago]

Originally Posted by teoman

- I have a copper pipe wrapped around the exhaust which heats up.
- I have an injector on one side, the injector is never heated and it has a heat-break (silicone tubing) to prevent that.
- The other side of the copper pipe is connected to the intake by hose (after MAF).

The injector shoots the water out which arrives at the pipe. As it evaporates, it expands. But it cannot escape by the route which it came from, it is blocked by the injector. So the only way to go is travel the copper pipe, then the hose in to the manifold.

My objective going this route, is to be able to control the intake air temperature precisely, keep it at an exact temperature range, instead of relying on it to suck up some unknown air temperature near the exhaust manifold.

You're going to want to force some airflow through your copper pipe, or it will quickly fill up with hot water, and you won't get your desired steam output. A good amount of insulation on that pipe is also called for.

[teoman]

Why would it fill up with water?

[teoman]

My objective is to keep it at exhaust temp so that any water i push in will instantly transform in to steam.

New steam will push the old steam out.