%0 Journal Article
%A Nazif, Hamid Reza
%A Tabrizi, Hassan Basirat
%D 2011
%I Begell House
%N 6
%P 499-508
%R 10.1615/InterJFluidMechRes.v38.i6.30
%T Comparison of Standard Turbulent Wall Function with a Non-Equilibrium Wall Model
%U https://www.dl.begellhouse.com/journals/71cb29ca5b40f8f8,6f481b230804413e,463440b670729733.html
%V 38
%X Non-equilibrium (NE) flows, which could occur in most of industrial problems, have some specific physical appearance. Wall bounded flow with severe adverse pressure, separation, reattachment and stagnation has NE exhibition. A wall function in turbulent flow is a remedy to resolving near wall complex phenomena using predetermined functions as boundary conditions. The advantage of this case is permission to using a relatively coarse near wall cells for saving CPU time. Standard wall function (SWF) is a semi-empirical function which is just valid for local equilibrium flows and constant shear stress at near wall cell. As the k-ε model is a simple but key way in simulation of complex and expensive industrial problems, in present study this turbulent model is employed with a non-equilibrium wall function. The simulation results are validated against ready (DNS) on channel and experimental data on backward facing step (BS). Prediction with this non-equilibrium wall function shows that using this wall approach in k-ε model has not made any sensitive change in equilibrium flow compared with SWF. However, produces effective improvement in NE conditions like flow in a backward facing step.
%8 2011-11-29