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8

Different vehicles use(d) different schemes. The S-IV stage on the Saturn I vehicle had overboard vents for the LH2, and fabric blowout panels for the LOX. One of the LH2 vents is indicated, the blowout panels are the half-ovals at the lower end of the stage. The Saturn V second stage used a recirculating chilldown system that didn't require overboard ...


5

It uses the cold nitrogen gas RCS thrusters. Sometimes, you can see them firing shortly before second stage engine startup. Elon Musk has talked about using the ullage gas vents as RCS thrusters and for propellant settling as well. He mentioned they are already using them to help deorbit the second stage. Super Heavy will not have separate RCS thrusters, it ...


2

This is known at autogenous pressurization https://en.wikipedia.org/wiki/Autogenous_pressurization The tanks are pressurized to help maintain structural integrity and to aid in the intake of propellant to the turbopumps. But pressurizing the propellant tanks is not the same as forcing the propellant into the combustion chamber. The exit pressures from rocket ...


2

For most rocket fuels calculating the specific energy (the energy released per unit mass), assuming a 100% conversion to kinetic energy (as this is a theoretical limit) and calculating velocity from that will give you a good estimate of specific impulse. If you want a better estimate you can adjust for energy lost from the enthalpy change of vaporisation and ...


1

I don't think that equation is correct. I don't see the benefits of using $I_{sp}$ when you have the thrust, $F_{t}$. The 1D equation of motion (neglecting drag) is: $a_{b}(t)=\frac{F_t}{m_0-\dot{m}t}-g$ $a_{c}(t) = -g$ Where $c$ and $b$ are the coast and boost phases of flight. Your burn rate, $\dot{m}$, assumption is good, and since it is a constant you ...


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