PLANE UNSTEADY FLOWS IN NOZZLES WITH DOUBLE RESTRICTIONS
Keywords:
unsteady flow, double-constriction nozzle, transonic flow, Laval nozzle, Weierstrass elliptic functions, sonic line, velocity potential, gas dynamicsAbstract
This article is devoted to the development of an analytical method for solving a plane initial-boundary value problem for unsteady transonic ideal gas flow in a Laval nozzle with two constrictions. The mathematical model is based on the classical nonlinear velocity potential equation for unsteady flows. The authors propose a method of separation of variables, which reduces the original problem to a system of ordinary differential equations whose solutions are expressed in terms of Weierstrass elliptic functions and Bessel functions. Various flow regimes are analyzed: the transition from subsonic to supersonic flow, the formation of local supersonic zones, and the occurrence of Taylor-Meyer flows in critical sections. Graphical dependences of the stream functions and pressure distributions are presented, confirming the adequacy of the model as time tends to infinity.
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