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In the lattice Boltzmann method (LBM), the widely utilized wall boundary isthe bounce-back (BB) boundary, which corresponds to the no-slip boundary. TheBB boundary prevents the LBM from capturing the accurate shear drag on the wallwhen addressing high Reynolds number flows using coarse-grid systems. In thisstudy, we proposed a "wall-function bounce (WFB)" boundary that incorporates awall function into the LBM's boundary condition and overcomes the limitation ofthe BB. The WFB boundary calculates the appropriate shear drag on the wallusing a wall function model, and thereafter modifies distribution functions toreflect the shear drag. The Spalding's law was utilized as the wall function inWFB. Simulations of turbulent channel flow at $Re_{\tau}$=640 and 2003 usingthe LBM-based large-eddy simulation (LBM-LES) were conducted to validate theeffectiveness of the proposed boundary condition. The results indicate that theBB boundary underestimated the time-averaged velocity in the buffer layer at$Re_{\tau}$=640, and the averaged velocity in the entire domain at$Re_{\tau}$=2003, when using coarse-grid systems. However, WFB obtained theproper shear drag on the wall and thus, compensated for the underestimation andagreed better with the experimental or DNS data, especially at the first-layergrid. In addition, WFB improved the Reynolds normal stress in the near-wallregion to some extent. The distributions of shear stress on the wall by WFB wasanalogous to those by the wall model function in the finite volume method.

A wall function approach in lattice Boltzmann method: algorithm and validation using turbulent channel flow