Advances in Aircraft and Spacecraft Science Volume 6, Number 1, January 2019 , pages 19-30 DOI: https://doi.org/10.12989/aas.2019.6.1.019 |
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Shock wave instability in a bent channel with subsonic/supersonic exit |
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Alexander Kuzmin
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Abstract | ||
Two- and three-dimensional turbulent airflows in a 9-degrees-bent channel are studied numerically. The inner surfaces of upper and lower walls are parallel to each other upstream and downstream of the bend section. The free stream is supersonic, whereas the flow at the channel exit is either supersonic or subsonic depending on the given backpressure. Solutions of the Reynolds-averaged Navier-Stokes equations are obtained with a finite-volume solver ANSYS CFX. The solutions reveal instability of formed shock waves and a flow hysteresis in considerable bands of the free-stream Mach number at zero and negative angles of attack. The instability is caused by an interaction of shocks with the expansion flow formed over the convex bend of lower wall. | ||
Key Words | ||
shock waves; curved channel; instability; hysteresis; turbulent boundary layer | ||
Address | ||
Department of Fluid Dynamics, St. Petersburg State University, 28 University Avenue, 198504, Russia | ||