Figure P9.136 is a special application of Prob. 9.135. With careful design, one can orient the bend

Question:

Figure P9.136 is a special application of Prob. 9.135. With careful design, one can orient the bend on the lower wall so that the reflected wave is exactly canceled by the return bend, as shown. This is a method of reducing the Mach number in a channel (a supersonic diffuser). If the bend angle is φ = 10°, find
(a) The downstream width h and
(b) The downstream Mach number. Assume a weak shock wave.

Figure P9.136 is a special application