Numerical simulation of the evolution of an intense aerodynamic jet in the far-field propagation

The conditions for the outflow of an underexpanded supersonic jet from the LTRAC experiment (Laboratory for Turbulent Research in Aerospace and Combustion, Monash University, Australia) are considered. The analysis of the characteristic parameters of linear and nonlinear transport for the LTRAC jet is carried out 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 were also obtained using the initial data from the LES calculation. Solutions were obtained without and in the presence of a term in the Burgers equation corresponding to quadratic nonlinearity. The solutions responded to sound transfer at distances that were orders of magnitude greater than the distance between the acoustic microphone and the jet in the LTRAC experiment.