Abstract
Large-Eddy Simulation (LES) is applied to examine the turbulent mixing and evolution in a stably stratified flow with a thermally sharp interface. Turbulent velocity intensities and turbulent kinetic energy are analyzed by considering the mean shear and stratification effects. The evolution of turbulent mixing layer and turbulent structures are mainly investigated. The results show that the streamwise intensities are much larger than the vertical intensities, and vertical fluctuations decay more rapidly at the presence of stratification. The qualitatively computational results suggest that the mixing layer, defined by the mean temperature, inclines to the side with small inlet velocity. The evolution of the half-width of the mixing layer shows two different slopes. The turbulent structure with high vorticity is restricted in the mixing layer especially in strong stratified cases.
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Project supported by the National Natural Science Foundation of China (Grant Nos. 10472063, 10742005), the Shanghai Pujiang Project for Talented Scholars(Grant No. 06PJ14041).
Biography: QIU Xiang (1978- ), Male, Ph. D.
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Qiu, X., Zhang, Dx., Lu, Zm. et al. Turbulent Mixing and Evolution in a Stably Stratified Flow with a Temperature Step. J Hydrodyn 21, 84–92 (2009). https://doi.org/10.1016/S1001-6058(08)60122-5
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DOI: https://doi.org/10.1016/S1001-6058(08)60122-5