Water Injection

Moderator: Mike Everman

Mike Everman
Posts: 4939
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

re: Water Injection

Post by Mike Everman » Thu May 11, 2006 4:43 pm

OK, keep going and you'll end up with what I'm doing! ha
I'll just tell you.
The outer jacket will not work for a flight system because the pressure will crush the pjet unless it is quite thick.
One aspect of what I'm doing is a flash boiler down the center of the tailpipe, with a rocket nozzle at the tail end. That way, you can use 3-400 psi steam with a fairly thin walled boiler. Art to post later!

Scavenging the heat from the outer wall of the pjet is the next bit, but my prototype is only using the above internal boiler.

This is why I was looking for steam nozzle designs a while ago.
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

Mike Everman
Posts: 4939
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

re: Water Injection

Post by Mike Everman » Thu May 11, 2006 5:14 pm

Here's the art. Increasing surface area and extracting more heat with tail expansion are metrics to work out.
Attachments
steamboy.jpg
steamboy.jpg (12.98 KiB) Viewed 5660 times
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

Eric
Posts: 1859
Joined: Sat Oct 04, 2003 1:17 am
Antipspambot question: 0
Location: United States
Contact:

re: Water Injection

Post by Eric » Thu May 11, 2006 5:52 pm

Mike are you having as much fun as I am listening to everyones ideas?

For efficiency, the overall consumption would be similar to the fuel consumption rate of the normal base pulsejet.

For max power a ton of water could be injected, but the best quantity that yeilds the most gain per volume of water is considerably less, well worth the increase in thrust, especially when coupled with other things.

I am not going to reveal the specifics of my preheating systems, but it does result in an engine that is warm to the touch :D

Oh and it doesnt use a pressure jacket, I would really really really avoid making a pressure jacket there are a ton of reasons not to use one, not including that they can be unsafe (aka explode), or potentially crush the engine.

Some people who are experienced with steam pressure systems will likely argue that it is easy to do, but if you are trying to get 300 - 400 psi like Mike there could be catastrophic results for the average self-taught-welding DIY'er who doesnt know any better.

Small diameter coiled tubing is definately the way to go, and it can withstand considerable pressure.
Image

Talking like a pirate does not qualify as experience, this should be common sense, as pirates have little real life experience in anything other than smelling bad, and contracting venereal diseases

Mike Everman
Posts: 4939
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

re: Water Injection

Post by Mike Everman » Thu May 11, 2006 5:58 pm

Agreed that coil heat exchangers are much safer, and of course where one would start if one were sane. On the safety subject, I am designing for 250psi limit for now. As I increase the pressure, at least if mine grenades, it's inside a steel shield!
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

Eric
Posts: 1859
Joined: Sat Oct 04, 2003 1:17 am
Antipspambot question: 0
Location: United States
Contact:

re: Water Injection

Post by Eric » Thu May 11, 2006 6:00 pm

Bah! Dont build one like that... they work horribly .... actually ... they dont work at all... yes .... they dont work at all
Image

Talking like a pirate does not qualify as experience, this should be common sense, as pirates have little real life experience in anything other than smelling bad, and contracting venereal diseases

Eric
Posts: 1859
Joined: Sat Oct 04, 2003 1:17 am
Antipspambot question: 0
Location: United States
Contact:

re: Water Injection

Post by Eric » Thu May 11, 2006 6:03 pm

Why not put a pressure release plug on it, so it will blow the plug before it blows the main tube.
Image

Talking like a pirate does not qualify as experience, this should be common sense, as pirates have little real life experience in anything other than smelling bad, and contracting venereal diseases

Mike Everman
Posts: 4939
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

Re: re: Water Injection

Post by Mike Everman » Thu May 11, 2006 6:07 pm

Eric wrote:Bah! Dont build one like that... they work horribly .... actually ... they dont work at all... yes .... they dont work at all
ha ah ha I think you're having fun with me!

Rest assured, I will have a pressure release in there somewhere.
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

tufty
Posts: 847
Joined: Wed Dec 24, 2003 12:12 pm
Antipspambot question: 0
Location: France
Contact:

Re: re: Water Injection

Post by tufty » Thu May 11, 2006 6:11 pm

Mike Everman wrote:Here's the art. Increasing surface area and extracting more heat with tail expansion are metrics to work out.
Man, that's beautiful.

Simon

francisco
Posts: 226
Joined: Tue Nov 30, 2004 1:06 pm
Antipspambot question: 0
Location: RIO CUARTO, CORDOBA, ARGENTINA

re: Water Injection

Post by francisco » Thu May 11, 2006 6:37 pm

hola, soy de argentina y tengo el agrado de conocer mucho sobre este tema, esto de al inyeccion de H2O en los pulsos, para argntina es algo viejo, este sistem fue patentado ena argenitna por gustavo mountafain, y es un sistema realmente facil de utilizar.

ventajas del sistema:

-aumente el 25% del empuje del motor
-reduce el consumo de cumbustible en un 10%
-reduce el ruido en un 14 a 18 %
-reduce la temperatura a unos 750°c
-no rompe margaritas por tiempos de hasta 63 hs

luego fijare mas informacion alrrespecto.


el los pulsos sin valvulas he utilizado el H2O para pruevas de fumigacion 3 litros de h20 se vacian el solo 15 minutos , en un lockwood de 1,5 kg de empuje.



hello, I am of Argentinean and I have the affability to know much on this subject, this of a the injection of HÒ in the pulses, for argntina is something old, this sistem was patented ena argenitna by gustavo mountafain, and is a really facil system to use. advantages of the system: - 25% increase of the push of the motor - the consumption of cumbustible in a 10% reduces - the noise in 14 reduces to 18 % - the temperature reduces to 750°c - hs does not break daisies per times of up to 63 soon alrrespecto will fix but information. the pulses without valve I have used the HÒ for pruevas of fumigation 3 liters of h20 vacian single the 15 minutes, in lockwood of 1.5 kg of push.



FRANCISCO COOREMAN
Attachments
pulsfogp.jpg
pulsfogp.jpg (15.08 KiB) Viewed 5630 times
swingfire_principle.gif
swingfire_principle.gif (11.42 KiB) Viewed 5632 times
Imagen136.jpg
Imagen136.jpg (16.65 KiB) Viewed 5629 times
Imagen135.jpg
Imagen135.jpg (12.98 KiB) Viewed 5628 times
Imagen137.jpg
Imagen137.jpg (14.08 KiB) Viewed 5629 times
"I DONT`T SUFFER OF MADNESS, I ENJOY IT CONTINUALLY"

fran_rio88@hotmail.com

Dang911
Posts: 395
Joined: Sat Jun 11, 2005 6:03 pm
Antipspambot question: 0
Location: USA-Florida, Georgia, Ohio
Contact:

re: Water Injection

Post by Dang911 » Thu May 11, 2006 8:16 pm

Ok, I am going to use a coiled water jacket, but could you explain the different water injection locations, and there respected performance enhancements.... Also how much water can the engine truly take on, do I need a bigger tube than 3/8" ID?
Louder is ALWAYS Better!!!

Bruno Ogorelec
Posts: 3542
Joined: Sat Oct 04, 2003 7:31 am
Antipspambot question: 0
Location: Zagreb, Croatia

Re: re: Water Injection

Post by Bruno Ogorelec » Fri May 12, 2006 11:16 am

Al Belli wrote:Hi Bruno,

Propane is slightly soluble in water, 65 cc/L.

Acetylene is a better choice at 1000 cc/L.

Source: CRC Handbook of Chemistry and Physics.

Al Belli
Thanks, Al!

The idea is, of course, to kill two birds with one stone.

Not a very simple solution -- engineers will cringe at the thought of a tri-propellant engine -- but since the engine is bog-simple itself, and the yield boost potentially huge, why not consider it? Fire the engine with diesel as the prime fuel and inject it with water laced with acetylene.

But -- a thought occurs to me as I write this -- once the engine is up and running with diesel, perhaps a water-diesel emulsion would work as both fuel and reaction mass.

Any opinions on that? I know that some piston engines have been run experimentally on gasoline-water emulsion but can't remember if anyone has ever done it with diesel.

Johansson
Posts: 1161
Joined: Sun Nov 21, 2004 9:42 pm
Antipspambot question: 0
Location: Northern Sweden

re: Water Injection

Post by Johansson » Fri May 12, 2006 11:28 am

What if the heat exchange coil was wrapped inside the CC instead of on the outside?

Since the intake/exhaust velocity is at its lowest in the CC it should not restrict the gasses much, and the heat exchange would be far greater since the entire surface area of the coil is subjected to the combustion heat instead of just the side that is closest to the CC or tailpipe.

Stainless is a lousy heat exchanger and most pulsejets are made of it, so it makes little sense to me to wrap the coil around the engine...

//Anders

tufty
Posts: 847
Joined: Wed Dec 24, 2003 12:12 pm
Antipspambot question: 0
Location: France
Contact:

Re: re: Water Injection

Post by tufty » Fri May 12, 2006 11:58 am

Johansson wrote:What if the heat exchange coil was wrapped inside the CC instead of on the outside?

Since the intake/exhaust velocity is at its lowest in the CC it should not restrict the gasses much, and the heat exchange would be far greater since the entire surface area of the coil is subjected to the combustion heat instead of just the side that is closest to the CC or tailpipe.

Stainless is a lousy heat exchanger and most pulsejets are made of it, so it makes little sense to me to wrap the coil around the engine...

//Anders
Well, if you're preheating water using the _internal_ heat of the engine, you gain very little over just injecting it cold - you're still using the heat internal to the engine to heat the water. If you are using the external "waste" heat of the engine you're effectively putting some of that energy back into the engine, no matter how inefficiently you're capturing it.

That's the way I see it, anyway. But I'm probably wrong.

Simon

Johansson
Posts: 1161
Joined: Sun Nov 21, 2004 9:42 pm
Antipspambot question: 0
Location: Northern Sweden

re: Water Injection

Post by Johansson » Fri May 12, 2006 12:04 pm

But the internal vapour coil would decrease CC wall temperature and therefore heat loss through the walls compared to an external heat coil where the heat exchange occurs after that the heat has traveled through the CC walls, so in my narrow mind it seems more effective to produce steam inside the engine.

The drawback is that the heat in the tailpipe cannot be used with this method.

//Anders

larry cottrill
Posts: 4140
Joined: Sun Oct 05, 2003 1:17 am
Antipspambot question: 0
Location: Mingo, Iowa USA
Contact:

Re: re: Water Injection

Post by larry cottrill » Fri May 12, 2006 3:13 pm

Mike Everman wrote:The outer jacket will not work for a flight system because the pressure will crush the pjet unless it is quite thick.
Mike -

A clarification: What I was originally proposing was NOT a reservoir of liquid water around the engine - it was just a small-volume jacket into which water would be sprayed through modrate-pressure nozzles. The idea was not to create pressure, but just add mass at a moderate velocity to the tailpipe exhaust stream. The water would be in a tank similar to the fuel tank, and driven in with a pump or air pressure. The vapor pressure in the jacket would be no more than the average chamber pressure.

L Cottrill

Post Reply