Numerical simulation of the development of Görtler vortices in compressible boundary layer on a concave surface
T.A. Gimon, V.A. Kislovskii, S.V. Lukashevich, S.O. Morozov, M.S. Nikolaev, A.N. Shiplyuk
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
Keywords: compressible boundary layer, laminar-turbulent transition, linear theory of stability, Gortler vortices, direct numerical simulation
Abstract
The generation and development of Görtler vortices in a compressible boundary layer on a concave surface has been numerically modeled. The calculation was carried out using the Fluent software of the Ansys program package. Stationary and non-stationary perturbations are analyzed at oncoming-flow Mach number M ≈ 4. It is shown that when a periodic disturbance in the direction transversal to the flow is introduced, it decays on the straight section of the surface, and grows on the concave surface. Comparison of the results of the calculations made with the calculations performed within the framework of the linear theory of stability showed that the range of susceptibility of the boundary layer to disturbances on the concave surface amounts approximately to 17 boundary-layer thicknesses. After the susceptibility zone, disturbances grow exponentially with small deviations. The flow fluctuation profiles are in good agreement with the data obtained from the linear theory of stability. It is shown that the development of a non-stationary perturbation along the surface of the model for the parameters considered in the present study differs little from that of a stationary perturbation.
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