Prandtl–Meyer function

Prandtl–Meyer function describes the angle through which a flow can turn isentropically for the given initial and final Mach number. It is the maximum angle through which a sonic (M = 1) flow can be turned around a convex corner. For an ideal gas, it is expressed as follows,

where ${\displaystyle \nu \,}$ is the Prandtl–Meyer function, ${\displaystyle M}$ is the Mach number of the flow and ${\displaystyle \gamma }$ is the ratio of the specific heat capacities.

By convention, the constant of integration is selected such that ${\displaystyle \nu (1)=0.\,}$

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