The Prandtl-Glauert parameter, often denoted as , is a dimensionless quantity used in aerodynamics to correct for compressibility effects in fluid flow, particularly when the flow approaches or exceeds the speed of sound. It is used to transform equations and aerodynamic coefficients that are valid for incompressible flow to account for the changes in flow behavior that occur as the Mach number () approaches and exceeds 1 (the speed of sound).
- β is the Prandtl-Glauert parameter