The problem of three-dimensional mode jet screech tones radiated by an imperfectly expanded supersonic cold jet is studied computationally using the general purpose CFD code ANSYS FLUENT, version 12. Pressure-based coupled solver formulation with the second-order bounded central-upwind spatial discretization and second-order implicit time marching scheme is applied to obtain a quasi-periodic transient solution. The numerical model reproduces physics of the jet screech tone feedback loop generation mechanism driven by interaction of large scale turbulent structures with jet shock cells. Propagation of flapping and helical mode disturbances along the jet column is recovered in the simulation. The acoustic near-field is resolved to accurately propagate screech tone waves to microphone monitors defined on the nozzle lip. Calculated screech tone frequencies and sound pressure levels are compared with experimental data, and favorable near-field agreement is found.
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