【摘 要】
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The application of grooved surface structure is an emerging and effective means in tur-bulence flow control.However,for a realistic configuration,the global flow field described directly by simple application of massive grids makes it unfeasible to simula
【机 构】
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Department of Aeronautics & Astronautics,Fudan University,Shanghai 200433,China;Department of Materi
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The application of grooved surface structure is an emerging and effective means in tur-bulence flow control.However,for a realistic configuration,the global flow field described directly by simple application of massive grids makes it unfeasible to simulate.In this paper,a boundary surrogate model reproducing the effect of microscopic near-wall region is proposed to improve computational efficiency.The surrogate model trained with Lattice Boltzmann Method (LBM) con-sidering the rarefied effect based on real micro/nanoflow field is new among literature,which accu-rately shows flow characteristics of the micro/nano structure.With this approach,numerical simulations via Reynolds-averaged Navier Stokes equations with modified wall boundary condition are performed in subsonic and transonic flow.The results show that micro/nano grooved surface structure has the effect of delaying transition from laminar to turbulence,thus reducing the skin friction significantly.Analysis of turbulence intensity and turbulence kinetic energy shows that the near-wall flow field of grooved airfoil is more stable compared with that of the smooth airfoil.The reducing rate of maximum turbulent intensity reaches 13.39％.The paper shows a perspective for further application of micro/nano groove structure to turbulence flow control in aircraft design by providing an accurate and efficient simulation method.
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