Small regen LOX/kerosene engines don't necessarily need film cooling. Maybe I
stumbled onto a successful operating region but neither of my aluminum engines
(100, 250 lbf) needed film cooling. I'm running rich which helps to soot the
walls more than normal. It did take a fair amount of analysis to get the
design to converge though.
But I agree that small cryo valves are a pain.
-Bob
On Dec 15, 2015, at 10:43, Paul Breed <paul@xxxxxxxxxx> wrote:
For a flight weight vehicle, its hard to build light weight LOX tanks, and
the valves for LOX are a continuous problem with
small valves.
Also if you factor in the price of Helium I think that peroxide pressurized
with Air or N2 is lower cost than LOX.
The Lox is almost free, the Helium not so much....
Also no hardstart issues, it just lights....
the O:F is ~ 7:1 and the O is the coolant for Regen, small Lox hydrocarbon
regen motors are hard and need film cooling,
with Persoxide I'm runing a 100lb regen aluminum motor with no cooling issues
(so far)
You do have cat pack issues...
You can get you oxidizer and store it for log periods... not so with Lox.
I like peroxide....
Paul
On Tue, Dec 15, 2015 at 8:31 AM, Monroe L. King Jr.
<monroe@xxxxxxxxxxxxxxxxxx> wrote:
Where there some details somewhere? Yeah, I think Paul had a better
source for peroxide than Armadillo seems like a lot of Armadillos work
was done with lower concentrations at least on the bigger motors.
Peroxide/gasoline or kero would seem to benefit from jet engine
technology. Basically treat it like a jet ingesting a lot of water. I
wonder if an annular combustion chamber can be made to withstand the
heat?
That would be reinventing the wheel right now which I'm wanting to
avoid.
-------- Original Message --------
Subject: [AR] Re: Peroxide/Gasoline Engine
From: David Weinshenker <daze39@xxxxxxxxxxxxx>
Date: Mon, December 14, 2015 10:00 pm
To: arocket@xxxxxxxxxxxxx
On 12/14/2015 08:07 AM, Monroe L. King Jr. wrote:
I was looking over the work done by amateurs on peroxide/kero rocket
motors.
What I see so far is a lot of unstable motors with asymmetrical issues.
Check out Paul Breed's peroxide/gasoline engine that flew on one of his
"lander challenge" vehicles: that seemed to be a smooth-running unit
(though well under the 1000 lbf. you contemplate here).
-dave w