A modified optimal LES model for highly compressible isotropic turbulence

ORAL

Abstract

An energy budget analysis and a posteriori tests of subgrid-scale (SGS) models for large eddy simulation (LES) of stationary highly compressible homogeneous isotropic turbulence are carried out at Mt ranging from 0.4 to 1.0 and Reλ ranging from 180 to 250. An energy budget analysis shows that the SGS stress τij and the SGS heat flux Qj are dominant terms in the current Mt and Reλ ranges, while other terms can be neglected in LES. We perform LES of compressible isotropic turbulence by using several SGS models including a DSM, a DMM, and an optimal model. In addition, a modified optimal model is constructed based on the magnitude of the filtered strain-rate tensor, inspired by the physical insight that the region of the large magnitude of the filtered strain-rate tensor plays a significant role in kinetic energy transfer. Spectra, statistics, and scaling of velocity and thermodynamic variables from LES are tested. The modified optimal model performs better than other models, especially for the spectrum of the compressible velocity component at relatively low Mt and high Reλ.

*This work was supported by NSFC Grant Nos. 11702127, 91752201, and 11672123; the Thousand Talents Plan for Young Professionals; Grant No. JCYJ20170412151759222; Grant No. 2016QNRC001.

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Presenters

  • Chenyue Xie

    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China

Authors

  • Chenyue Xie

    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China

  • Jianchun Wang

    • Southern University of Science and Technology, China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China

  • Hui Li

    • School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, P. R. China
    • School of Power and Mechanical Engineering, Wuhan University, Wuhan, Hubei 430072, P. R. China

  • Minping Wan

    • Department of Mechanics and Aerospace Engineering Southern University of Science and Technology
    • Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, Shenzhen 518055, China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China

  • Shiyi Chen

    • Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, State Key Laboratory for Turbulence and Complex Systems and Center for Applie
    • Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, Shenzhen 518055, China, State Key Laboratory for Turbulence and Complex Syste
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, State Key Laboratory of Turbulence and Complex
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China, State Key Laboratory of Turbulence
    • Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, State Key Laboratory for Turbulence and Comple