The Numerical Solution of Choked and Supercritical Ideal Gas Flow through Orifices and Convergent Conical Nozzles

Abstract

The paper describes the numerical solution of the equations of compressible flow through axisymmetric convergent nozzles. The class of supercritical flows is considered, in which the gas velocities in the jet downstream from the throat are supersonic. The subsonic region of the flowfield is solved in the hodograph plane by a finite-difference method. The supersonic region is solved in the physical plane by the method of characteristics. The stream function distribution on the sonic line is adjusted iteratively to match the boundary conditions at the lip and free streamline. Discharge coefficients are evaluated and truncation errors in the results are considered.