1. consider the flow of air through a convergent-divergent nozzle with a throat cross-section at = 0.4m2 and an exit-to-throat area ratio of 1.616. assuming that the reservoir conditions are p0 = 5.5 · 105p a and t0 = 550◦c, determine the exit mach number me and the mass flow ˙m through the nozzle when the pressure outside the reservoir pa attains the following values:
(a) pa = 5.0 · 105p a.
(b) pa = 2.2 · 105p a.
(c) pa = 0.4 · 105p a.
(d) draw the pattern of shocks and expansion waves at the nozzle exit for the last case.
2. in low-speed incompressible flow, the peak pressure coefficient (at the minimum pressure point) is cp = −0.48. estimate the critical mach number for the given airfoil, using the prandtl-glauet rule.