Strongly implicit methods for calculation of spatial flows of gas in nozzles

A new modified strongly implicit method for numerical solving of the system of algebraic equations obtained at the symmetric approximation of a linear elliptical equation in partial derivatives with respect to three independent variables using a 19-point three-dimensional grid pattern is developed. On the basis of this method an algorithm of the calculation of three-dimensional nozzle gas flows is developed and implemented; the algorithm possesses a higher convergence rate as compared with similar numerical techniques. Gas flows in nozzles with various geometric parameters are studied; in particular, thrust characteristics of nozzles with rectangular exit section are investigated.