Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 11, 2020 - November 13, 2020
The issues of the interaction between a normal shock wave and a boundary layer are very important in a variety of high-speed aerodynamic applications. Under certain operating conditions the unsteady flows with shock wave oscillations are widely observed in various fluid machineries including supersonic intakes, supersonic diffusers or nozzles, and supersonic ejectors, strongly affecting local heat transfer rates as well as aerodynamics loading. In addition, extreme pressure fluctuation, which is caused by the shock oscillation, induces vibration of the machineries. Understanding and predicting shock oscillation phenomena have stimulated previous many experimental and numerical studies. However, the mechanism of shock oscillations is still elusive. In this study, two-dimensional unsteady behavior produced by the interaction of a shock wave with a turbulent boundary layer in a transonic diffuser is investigated by the detached eddy simulation (DES). The diffuser model used in the present study has heights of 18 mm at the inlet, 6 mm at the throat, and 12 mm the exit. The diffuser flow is demonstrated using time-dependent density contour maps with typical streamlines to investigate the flow features of unsteady shock behavior.
