Mach number wind tunnel

A flat plate with a length of 0.8 m and a width of 1.2 m is placed in the working section of a wind tunnel in which the Mach number is 4, the temperature is -70°C, and the pressure is 3 kPa. If the surface temperature of the plate is kept at 30°C by an internal cooling system, And the rate at which heat must be added to or removed from the plate. Consider both the top and the bottom of the plate. 

The data collected during the test program consist of the fluid injection and wind tunnel parameters corresponding to the spark-shadow photographs. Water and air were used as the test fluids. Data were gathered for different sizes of injector nozzles at various levels of injection pressure and tunnel Mach number. Different injection angles also were examined. 

Air flows through a supersonic wind tunnel see Fig. 8.17. The flow is steady and isentropic, except that somewhere in the system there is a normal shock wave. If AjM I =1.01 and M = 1.0 at both A and A2, what is the upstream Mach number at the place where the normal shock occurs ... 

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