> True, but you can have the pressure in the tank bigger than in the combustion chamber, right?
I guess you can if people have done it. I've never built a rocket myself, so I don't know, but I thought the combustion-chamber pressure had to be crazily high to get the high exhaust velocity you need for propulsion.
Surprisingly you don't need to have that large of the pressure in the chamber to get to the sonic speed in the throat - and more than that in the diverging nozzle. E.g. 3 bar pressure in the chamber could be enough for that.
French Diamant rocket, the one used to launch their first satellite, had a pressure-fed first stage. Lunar Expedition Module from Apollo program had a pressure-fed ascent stage.
I guess you can if people have done it. I've never built a rocket myself, so I don't know, but I thought the combustion-chamber pressure had to be crazily high to get the high exhaust velocity you need for propulsion.
Thank you very much for enlightening me!