Turbulent Length Scale for Multilayer RANS Model of Urban Canopy and Its Evaluation Based on Large-Eddy Simulations


  • Andrey V. Glazunov G.I. Marchuk Institute of Numerical Mathematics, Russian Academy of Science
  • Andrey V. Debolskiy Lomonosov Moscow State University
  • Evgeny V. Mortikov Lomonosov Moscow State University https://orcid.org/0000-0002-9683-5701




atmospheric boundary layer, numerical simulation of turbulence, urban canopy, scalar turbulent transport


Large-Eddy Simulation (LES) numerical experiments of neutrally-stratified turbulent flow over an urban-type surface and passive scalar transport by this flow are performed. A simple parameterization of the turbulent length scale containing only one empirical constant is proposed. Multilayer Reynolds-Averaged Navier-Stokes (RANS) model of turbulent flow and turbulent scalar diffusion is constructed. The results of the RANS model are compared with the LES experiments. It is shown that the proposed approach allows predicting the average flow velocity and the scalar concentration inside and above the urban canopy.


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How to Cite

Glazunov, A. V., Debolskiy, A. V., & Mortikov, E. V. (2022). Turbulent Length Scale for Multilayer RANS Model of Urban Canopy and Its Evaluation Based on Large-Eddy Simulations. Supercomputing Frontiers and Innovations, 8(4), 100–116. https://doi.org/10.14529/jsfi210409