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Hybrid Fuel

Posted: Mon Sep 04, 2006 6:59 am
by LucyInTheSky
If a hybrid had a chamber of say 100ci, then you would need 16ci for a 4x mix (approx)?
So for a propane metre would you use a larger one than for a combustion or would you increase the pressure?
So you would put in a 4x the amount of propane needed in a regualer combustion then pump it up to 44.1PSI?

Posted: Mon Sep 04, 2006 10:04 am
by dongfang
See my computations in the previous thread, and plug in your numbers.

Sören

Posted: Mon Sep 04, 2006 11:28 am
by noname
1st question:
I have no idea.
2nd question:
Just inject the same ammount of propane 4 times.
3rd question:
Yes.

I know you don't like PVC, and that's good, especially if you plan to make a hybrid that you're going to put to 4x.

Posted: Mon Sep 04, 2006 12:42 pm
by LucyInTheSky
Do you NEED a regulater to measur the right amount of propane?

Or can you just fit a pressure gauge in the meter then let xPSI into the meter with a ball valve?

Posted: Mon Sep 04, 2006 1:06 pm
by SpudStuff
You Need A regulator

Posted: Mon Sep 04, 2006 1:13 pm
by Pete Zaria
Lucy,
I use the method you just described. I have a pressure gauge in my meter pipe. I turn on the valve from the propane tank, wait for 38 PSI in the meter (the correct pressure for a 4.2% propane mix in my chamber), close the first valve, and then open the second one to vent the gas in the meter into the chamber. Works fine for me. You just have to close the first valve quickly, when the gauge reaches the correct pressure.

However, my setup is on a combustion, not a hybrid. I'm designing a steel hybrid which I intend to build early next year, though.

Peace,
Pete Zaria.

Posted: Mon Sep 04, 2006 1:17 pm
by SpudStuff
You need an EXACT mix. a couple PSI cancause a malfunction and it won't fire.

Posted: Mon Sep 04, 2006 1:19 pm
by LucyInTheSky
Can you use a BBQ igniter for ignition? If you made the spark gap smaller so it would still spark.

Posted: Mon Sep 04, 2006 3:16 pm
by Shrimphead
If I were you, I would use a stun gun. The bbq sparker won't have too big of a spark under pressure (I think). You might as well pay a few dollars more and get a stun gun for a much more reliable ignition.

Posted: Mon Sep 04, 2006 3:23 pm
by LucyInTheSky
Ok thanks.

Would this regulator work? How do you set the pressures for one?

http://www.airlines-pneumatics.co.uk/we ... de=S050138

Posted: Mon Sep 04, 2006 3:28 pm
by LucyInTheSky
Also would it be better to have a larger meter with lower pressures or vice versa?

Like, 1x at 10psi 2x at 20psi 3x at 30psi

or 1x at 20psi 2x at 40psi 3x at 60psi?

How much pressure do propane tourches put out?

Should I can a 0-6bar reg or a 0-10bar reg?

Posted: Mon Sep 04, 2006 6:30 pm
by noname
A smaller meter is cheaper but it doesn't really matter.
Propane in bottles is only like 90-100 psi, I'm pretty sure. I don't know bar so I can't help you there.

Posted: Mon Sep 04, 2006 6:38 pm
by SpudStuff
Propane liquifis at 90 PSI You should use a low pressure meter with a large pipe. Get the 10 Bar Reg as then you can use it for the air as well. You ajust the Reg by turning the large knob on the top.
No Name: 1 Bar = 14.7 PSI=1 Atmosphere.

Posted: Mon Sep 04, 2006 8:05 pm
by noname
That's easy for hybrids then. Just measure out exactly 3 bar and inject the propane.

Posted: Mon Sep 04, 2006 9:44 pm
by SpudStuff
You mean Just inject the propane and then measure out exactly 3 bar.