A finite element analysis of a two-dimensional asymmetric relaxing channel flow by the k-epsilon model

Two types of modified boundary condition are presently adopted to improve the standard k-epsilon turbulence model: (1) the condition on the kinetic energy in the wall layer, where the kinetic energy equation is used to close the system of equations, and (2) the condition on the streamwise mean velocity component. It is assumed that the Karman constant remains unique in the direction normal to the wall, while varying in the streamwise dimension. Mean velocity profiles were well predicted; when the kinetic energy equation is expressed in the difference form and used as the wall boundary condition, the results show a reasonably gradual kinetic energy decrease.