Calculate the expansion fan properties for supersonic flow around a convex corner.
Flow Parameters
Calculation Results
Enter supersonic Mach and angle
Overview
Prandtl-Meyer expansion fans occur when supersonic flow turns away from itself (around a convex corner). The flow accelerates and the Mach number increases.
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Pro Tips
The Prandtl-Meyer function describes the angle through which the flow must turn to reach a specific Mach number from M=1.
γ is usually 1.4 for air.
The deflection angle θ is given by ν(M2) - ν(M1).
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Fun Facts
"Unlike shock waves, expansion fans are isentropic, meaning they don't cause a loss in total pressure."
"The maximum possible turn angle for air (γ=1.4) starting from M=1 is about 130.45°."
"Expansion fans are common at the trailing edges of supersonic airfoils."
