Questions tagged [thermodynamics]
The thermodynamics tag has no usage guidance.
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Typical external temperature profile for a LEO satellite
I bumped into a question regarding LEO orbit.
Is an external temperature profile available in literature as a first approximation for thermal analysis? I bumped into articles mentioning that the ...
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Satellite Surface Temperature in Orbit
I am trying to calculate the satellite surface temperature in Orbit for Thermal Tests of our satellite.
Referring "Space Vehicle Design, D.Griffin, Ch.9, the equations of heat transfer on the ...
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Resources for Rocket Propulsion
I am a Mechanical Engineering student who is very much interested in Rocket propulsion. Lately I have been searching for good resources to learn concepts about rocket propulsion. I'd be glad to get ...
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Temperature distribution of air around a rocket
I am doing some simulations in ANSYS Fluent of a rocket traveling at speed of 100 m/s at an altitude of 12000 m where the surroundings temperature is 216.7 K. The image above is the temperature ...
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What are the Specific heat ratios of fluorine, Isopropyl Alcohol and Uranium?
I needed to calculate thrust and velocities of a rocket engine and its exhaust and in order to do that, I needed the values of Specific heat ratio(k) of Fluorine and k of Uranium and Isopropyl Alcohol....
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How do I calculate thermochemical properties of mixed gases?
I'm working on a rocket project, and my design of engines is stalled. I need to be able to calculate the Cp, Cv, and R for mixtures of O2/CH4 (stoichiometric or fuel-rich mix) and CO2/H2O (result of ...
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Specific Heat Ratio for a perfect gas mixture
I am reading Rocket Propulsion Elements by George P. Sutton & Oscar Biblarz, 9th Edition. In the fifth chapter, I was introduce to the specific heat ratio k for the perfect gas mixture, Eq. 5-7:
(...
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Could a steam engine work on the moon? [closed]
Recently, there was a thread on Hacker News about building a nuclear power plant on the moon.
Humans being what they are, I could imagine some dark outcomes. Instead could we build a steam engine on ...
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Why would one assume chamber pressure instead of chamber volume when designing a rocket engine?
Most modern rocket analysis methods can base calculations on either Gibbs free energy or the Helmholtz free energy when computing what the exhaust products (and hence, the exhaust velocity) will be (...
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Relating Rocket Propellant Selection to Specific Impulse
Is it possible to directly relate a fuel/oxidizer selection to specific impulse at vacuum? I have tried a few different methods, but cannot seem to directly relate the two.
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Rocket Performance
I am just trying to do a simple rocket performance analysis. I want to determine specific impulse (vacuum isp) as a function of oxidizer to fuel ratio (O/F) for a LOX/LH2 engine and LOX/CH4 engine. I ...
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Rocket Combustion
How is the chamber pressure is arrived at for a given combustion temperature and mixture ratio ?
Based on the mixture ratio, the value of gamma and temperature can be found out, using chemical ...
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Which theory does this reentry heating rate equation come from?
The paper by Wang et al. at Scitech 2018 uses the following constraint on the rocket heating rate (equation (3) in the paper):
$$k_Q \sqrt{\rho} V^{3.15} \le \dot{Q}_{max}$$
(screen shot)
I am ...
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Are regneratively cooled nozzles still modeled as isentropic flow?
In a regeneratively cooled nozzle, there is a transfer of heat from the expanding exhaust to the nozzle (and then into the propellant cooling the nozzle). This is clearly not an adiabatic process. Is ...
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Is there some fundamental limitation that would prevent steam-powered rockets from reaching space?
According to the Discovery Channel (see CNN article below) the latest attempt to use compressed steam propulsion to get to 5000 feet ended in tragedy. It's not yet clear the altitude it reached, ...
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