# Tag Info

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To copy the key part of this answer (and this related earlier answer)... an important figure of merit in a rocket engine is the "characteristic velocity": $$c_* \propto \sqrt{\frac{T_t}{M_w}}$$ where $T_t$ can be taken to be the exhaust temperature, and $M_w$ is the molecular weight of the gas species in the exhaust. (The "proportional" ...

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Simply because the rewards aren't all that great, and haven't merited the added complexity. The potential improvements of tri-propellant mixes are limited by fairly simple chemistry (especially once you eliminate the options with toxicity or cost issues), and to get them you're adding another tank, another pump, more plumbing, all of which adds dry mass that ...

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Al = aluminum is a solid metal, RP1, O2 and H2 are stored as liquids within the tanks of a rocket. If you know a method to store a liquid preparation of aluminum that may be pumped into a rocket tank and after ignition pumped into a combustion chamber, we all here would like to read about it. Molten hot alumium is not useful in a rocket tank, it needs ...

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Use a mass-weighted average, e.g. $$C​_{p_{mixture}}​​= ​\frac{m_1}{m_{mixture}}​​​​ C​_{p_1}​​+ ​\frac{m_2}{m_{mixture}}​​​​ C​_{p_2}$$ Source: Rule of Mixtures Calculator for Heat Capacity May not apply depending on what you actually mean by vague proportions and unknown quantities obviously you have to know something.

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I think the answer is possibly yes, but the place to look is probably solid-fueled rockets not liquid-fueled ones. I am not a chemist but I believe it is the case that ammonium nitrate is used as an oxidiser in some such propellants: Wikipedia also seems to think so and says such mixtures are often known as 'ANCP'. Well, if you do the right thing to ...

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Some rockets (especially hybrids) use nitrous oxide oxidizer, which exothermically decomposes into nitrogen and oxygen and is capable of detonation. This is not just a theoretical hazard, Virgin Galactic experienced an explosion during a cold-flow injector test in 2007 that killed 3 people and injured 3 more. Acetylene is typically handled as a solution in ...

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As a rule of thumb, no rocket fuel (or oxidizer) will ever be able to detonate on its own. For the simple reason that the maximum flame front propagation through it needs to be slower than the fluid speed through the injectors, otherwise the flame would propagate back into the tanks. NO, no-one has ever managed to pump flammable fluids faster than their ...

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The Multi-Mission Radioisotope Thermoelectric Generators (MMRTG) used by NASA are probably unfeasible for the purposes you are thinking of, although they are highly useful for space exploration. Multiple spacecraft have used these, including both Voyager 1 and Voyager 2, New Horizons, Curiosity, and the new Perseverance. This is due to their ability to ...

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