Compressible Flow Questions & Answers  




But if $M_2=1$, then $T_2$ will have a different value than the one you computed..




I guess you refer here to the last problem of the last assignment. If so, then yes your reasoning is correct. The only thing missing in your reasoning is that you need to first assess whether the first oblique shock is weak or strong by looking at the wave pattern.. If there is a reflected shock, then for sure the first oblique shock is weak because a strong oblique shock would lead to a subsonic flow, hence preventing a shock reflection.




In 1D (as schematized in the midterm exam Q3), it's definitely possible to have an inlet with no shock. In 2D, you could design the inlet so that the flow slows down isentropically to Mach 1 through a Prandtl Meyer compression fan. In practice this is hard to achieve because such a design would only work for one specific Mach number and lead to major losses in performance at slightly different Mach numbers. Thus, inlets generally have several shocks to allow for some variation in geometry. But this is not mentioned (or schematized) in the question statement, so you can assume the flow isentropic through the inlet here.




I corrected the answers. Check again.



$\pi$ 