Numerical simulation of three-dimensional supersonic jet screech tones

A three-dimensional computational aeroacoustic procedure is developed to simulate the screech phenomenon from a supersonic circular jet. The 3D Navier-Stokes equations and a modified two equations standard k - ε turbulence model are solved in the generalized curvilinear coordinate system. The dispersion-relation-preserving scheme is utilized for space discretization. The 2N storage low-dissipation and low-dispersion Runge-Kutta scheme is applied for time marching. Numerical results are presented at Mach number 1.38, 1.42 and 1.43 for two nozzle exit lip thicknesses of 0.625-in. and 0.4-in. It is shown that the predicted wavelengths of the flapping and helical modes are in good agreement with experimental data by Ponton & Seiner. The predicted shock cell structure and radial density profiles agree well with the measured results by Panda & Seasholtz. And the simulated non-axisymmetric screech flapping phenomenon is also analyzed and qualatively compared with the acoustic measurement data by Ponton & Seiner.