Re: Liquox

At 06:59 PM 6/4/2004 +0200, you wrote:
>   John Carmack wrote:
>
>   > We are considering mixed-monoprop + liquid catalyst for building huge
>   > engines (20,000 lb thrust) where solid catalyst would cost fifteen
>thousand
>   > dollars or so.
>
>   Changing from heterogenous to homogenous HP decomposition is not a small
>step.
>
>   Could you give an idea of the mixed monoprop composition intended? Are we
>still talking 50 % H2O2?
>
>   In which case you'd probably equally use glowplugs to ignite the alcohol
>in the approx. only 200°F decomposition products.
>   Of which a large part initially 'll consist of oxygen and the rest of
>*wet* steam. Have you been able to ignite such so far?
>
>   JD

All of our engines and vehicles for the last year have been 50% peroxide + 
methanol mixed monoprop, running slightly lean of stoichemetric.  We have 
done several hundred firings, with up to 120 second burns, 145 s measured 
Isp, and 3700 lbf motors.  It does actually work.  It is superior to 90% 
peroxide monoprop in every way (cost, availability, performance, handling) 
except for startup characteristics and motor size.  We used glow plugs for 
a while, but spark plugs work better.  Once the bottom catalyst pack is up 
to temperature, the extra ignition source is no longer required.

John Carmack