Numerical Simulation of Turbulent Separated and Reattaching Flows by Local Forcing

- Journal title : Transactions of the Korean Society of Mechanical Engineers B
- Volume 24, Issue 3, 2000, pp.467-476
- Publisher : The Korean Society of Mechanical Engineers
- DOI : 10.22634/KSME-B.2000.24.3.467

Title & Authors

Numerical Simulation of Turbulent Separated and Reattaching Flows by Local Forcing

Rhee, Gwang-Hoon; Sung, Hyung-Jin;

Rhee, Gwang-Hoon; Sung, Hyung-Jin;

Abstract

An unsteady numerical simulation was performed for locally-forced separated and reattaching flow over a backward-facing step. The local forcing was given to the separated and reattaching flow by means of a sinusoidally oscillating jet from a separation line. A version of the model was employed, in which the near-wall behavior without reference to distance and the nonequilibrium effect in the recirculation region were incorporated. The Reynolds number based on the step height (H) was fixed at , and the forcing frequency was varied in the range . The predicted results were compared and validated with the experimental data of Chun and Sung. It was shown that the unsteady locally-forced separated and reattaching flows are predicted reasonably well with the model. To characterize the large-scale vortex evolution due to the local forcing, numerical flow visualizations were carried out.

Keywords

Low-Reynolds-Number Turbulence Model;Separated and Reattaching Flow;Local Forcing;Vortex Merging;

Language

Korean

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