On using the wall function and the staggered grid arrangement at upwind sharp convex corners in simulating approach air flow

In simulating approach air turbulent flow towards a cube or a square rib with staggered grids, there might be problems in using wall function. This point will be studied in this paper. Upwind sharp convex corners will be analyzed in detail. Methods are proposed to give predicted results, which agree better with experiments. The value and position of the maximum turbulent kinetic energy k(max) , and the mean pressure coefficient C-p are proposed to be correlated with the degree of separation and reattachment length Z(R) at the top of the bluff cube and rib for evaluating the predicted results. The standard k - epsilon model is suitable for predicting the degree of separation at the frontal sharp convex corners and reattachment length, provided that the wall functions are applied properly.