Which inlet design of supersonic jet engine is preferable?
A normal shock inlet forms a normal shock ahead of the inlet, with an attendant large loss in total pressure. In contrast, an oblique shock inlet creates an oblique shock wave, and the flow subsequently passes through a relatively weak normal shock at the lip of the inlet. For the same flight conditions (Mach number and altitude), the total pressure loss for the oblique shock inlet is less than for a normal shock inlet. Hence, everything else being equal, the resulting engine thrust will be higher for the oblique shock inlet. Therefore, oblique shock inlets are preffered.
How to Calculate Pressure Ratio across Oblique shock?
Pressure Ratio across Oblique shock calculator uses Pressure ratio across shock = 1+((2*Specific Heat Ratio Dynamic)/(Specific Heat Ratio Dynamic+1))*((Component of upstream mach normal to oblique shock^2)-1) to calculate the Pressure ratio across shock, Pressure ratio across oblique shock formula is obtained by substituting the normal component of upstream Mach no. in the pressure ratio formula for the normal shock. Pressure ratio across shock is denoted by Pshock_{ratio} symbol.
How to calculate Pressure Ratio across Oblique shock using this online calculator? To use this online calculator for Pressure Ratio across Oblique shock, enter Specific Heat Ratio Dynamic (κ) & Component of upstream mach normal to oblique shock (M_{n1}) and hit the calculate button. Here is how the Pressure Ratio across Oblique shock calculation can be explained with given input values -> 4.492433 = 1+((2*1.392758)/(1.392758+1))*((2^2)-1).