Effects of Wall-Temperature Conditions on Effusion Cooling in a Mach-2.67 Boundary Layer
نویسندگان
چکیده
The influence of effusion cooling through discrete holes on a laminar Ma-2.67 boundary layer is investigated using direct numerical simulation (DNS). It is found that the wall condition, isothermal, adiabatic or radiation-adiabatic, with neglected heat conduction within the wall, has a very strong influence on the vortex systems that are generated by the holes and thus also on the cooling features. The transfer of results from short-duration, isothermal shock-tunnel experiments to the more realistic, radiation-adiabatic situation is difficult. Besides trying to establish a coolant film at the wall a significant increase of the wall shear should be avoided in order not to increase the heat flux into the wall.
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