Stagnation Point Heating - enthalpy at the wall

roldy

Using the Fay-Riddell correlation, I can solve for the stagnation point heat transfer but I'm running into a snag. I'm doing this for a thermo-chemical equilibrium assumption. I'm confused with the enthalpy at the wall. I'm assuming a wall that is not adiabatic, but at some wall temp Tw. If I know what the pressure and density of the flow at the wall, could I use the eqair applet http://www.dept.aoe.vt.edu/~devenpor/tgas/ and solve for the enthalpy using the pressure and density as the inputs? I've posted an example from class.

I thought that I could use this but when I tried it and it didn't work out as I had planned. Following the example that my professor posted, he assumed that the enthalpy at the boundary layer edge (h_e) is the same as the enthalpy right after the shock wave (h₂). The enthalpy after the shock wave was found using the eqair applet.

I'm I correct in using the eqair applet again for the wall?

I tried working the example problem but I am not getting the results that my professor is getting. I tried using the eqair applet for using the wall conditions. and I get h wall = 1.6227E6. I solved his example in reverse to solve for the h wall that he is using and I get h wall = 2.469999778E7. He doesn't show what value he is using for the wall enthalpy.

Attached Files

sp_eq_example.pdf (606.1 KB, 3 views)