INFLUENCE OF WALL SHEAR STRESS ON THE SECONDARY FLOW IN SQUARE DUCTS

We investigated turbulent duct flows with a square cross section using well-resolved large-eddy simulations (LES). A physically consistent subgrid-scale turbulence model is incorporated, that is based on the Adaptive Local Deconvolution Method (ALDM) for implicit LES. The wall shear stress is artificially modified at one of the four walls to mimic different surface properties. A direct numerical simulation (DNS) of a symmetrical duct flow is used as reference to asses the influence of a modified wall shear stress. The modification results in an asymmetrical distribution of the secondary flow source terms, affecting the momentum distribution. Further, the anisotropy of the Reynolds stress tensor, which induces the secondary flow vortices is considerably affected by the wall shear stress change. © 2022 12th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2022. All rights reserved.     «

We investigated turbulent duct flows with a square cross section using well-resolved large-eddy simulations (LES). A physically consistent subgrid-scale turbulence model is incorporated, that is based on the Adaptive Local Deconvolution Method (ALDM) for implicit LES. The wall shear stress is artificially modified at one of the four walls to mimic different surface properties. A direct numerical simulation (DNS) of a symmetrical duct flow is used as reference to asses the influence of a modified...     »