Numerical Simulation of the Evolution of an Intense Aerodynamic Jet in the Far-Field of Propagation

The conditions for the outflow of an underexpanded supersonic jet from an experiment conducted at the Laboratory for Turbulent Research in Aerospace and Combustion (LTRAC), Monash University, Australia are considered. The characteristic parameters of linear and nonlinear transport for the LTRAC jet are analyzed using LES solutions from the near and far acoustic fields. In both cases, the fulfillment of the conditions of the linear scenario of sound transfer over distances characteristic of the LTRAC acoustic experiment is shown. To verify the theoretical estimates, numerical solutions of the spherical Burgers equation are also obtained using the initial data from the LES calculation. Solutions are obtained without and in the presence of a term in the Burgers equation corresponding to quadratic nonlinearity. The solutions respond to sound transfer at distances that are orders of magnitude greater than the distance between the acoustic microphone and the jet in the LTRAC experiment.