Effect of Different Near-Wall Treatments on Indoor Airflow Simulations

Airflow simulation results depend on a good prediction of near wall turbulence. in this paper a comparative study between different near wall treatments is presented. it is applied to two test cases in building: (1) the first concerns flow through a long corridor which is similar to that in a fully developed plane channel. simulation results are compared to direct numerical simulation (dns) data of moser et al. (1999) for reτ = 590 (where reτ denotes the friction reynolds number defined by friction velocity uτ , kinematics viscosity í and the channel half-width δ); (2) the second case is a benchmark test for room air distribution. simulation results are compared to experimental data obtained with laser-doppler anemometry (nielsen, 1990). simulations were performed with the aid of cfd code fluent (2005). near wall treatments available in fluent were tested: standard wall functions, non equilibrium wall function and enhanced wall treatment. in each case, suitable meshes with adequate position of the first near-wall node are needed. results of near-wall mean stream wise velocity u+ and turbulent kinetic energy u+ profiles are presented, variables with the superscript of + are those non dimensional by the wall friction velocity uτ and the kinematic viscosity ν.