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I'm looking for a way to (very) roughly estimate the convective heat transfer onto a rocket hull during atmospheric ascent (ideally through different planetary atmospheres). While I'm comfortable with most of the necessary variables, the heat transfer coefficient h seems to be a bit of a problem since it depends on a range of different parameters (Prandtl, Reynolds,...) that continuously change during the ascent.

Although I'm aiming for a simple and highly idealized approach, I fear that too much estimation adds up to a worthless solution.

I'm probably not the first person to think about that topic. Do you know of any links, papers, etc. to get me started?

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  • $\begingroup$ "I'm probably not the first person to think about this topic." Lol. $\endgroup$ – Organic Marble Jun 30 '15 at 15:12
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    $\begingroup$ It was meant to be a joke - but as I'm not a native speaker that maybe didn't work out to well :/ Besides sophisticated numerical approaches, estimating the heat transfer coefficient should be a common problem in preliminary design for all types of (flying) vehicles. How did our grandfathers deal with this? $\endgroup$ – cl10k Jun 30 '15 at 16:20
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    $\begingroup$ It was clearly a joke and I was appreciating it. $\endgroup$ – Organic Marble Jun 30 '15 at 16:31
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I would treat it as a forced convection over a vertical plate and unfortunately, you will have to at least scale by the density of the atmosphere and velocity, both of which will vary greatly during ascent. Atmospheric temperature will be set by the shock heating after you go supersonic, but don't forget the large temperature variation in the static atmosphere which is your starting point. A simple spreadsheet should help there though. Good luck.

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  • $\begingroup$ This is quite correct. Natural air convection at typical speeds of motion of the rocket becomes completely negligible, lost as rounding error in supersonic wake turbulence. Effects of change of ambient temperature (crucial for ram rise and varying quite wildly with altitude!) and pressure with altitude, and distribution of pressure and the flow over the surface due to aerodynamic profile of the rocket. This should provide some starting points and terms related to the problem for future search. $\endgroup$ – SF. Dec 13 '19 at 3:57

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