Direct numerical simulation of supersonic jet flow (Q1392603)

A numerical method is given for direct numerical simulation of the nonlinear evolution of instability waves in supersonic round jets, with spatial discretisation based on high-order compact finite differences. We analyse numerical properties of a class of symmetric and asymmetric schemes, and discuss the implementation of the Navier-Stokes equations in cylindrical polar coordinates with particular attention to the treatment of the origin to ensure stability and efficiency. The computer code is applied to study the initial stages of nonlinear development of unstable modes in a Mach 3 jet.