Abstract
This paper describes the numerical study of a non-stratified airflow past a two-dimensional escarpment in a uniform flow. The Reynolds number, based on the uniform flow and the height of the escarpment, is about 104. The slope gradient of the escarpment is 25, 35 and 45 degree. Attention is focused on an influence of a slope gradient on airflow characteristics in a wake region. Through comparison between the numerical results, the significant difference in the airflow characteristics is confirmed in the wake region. This is mainly due to the size in the separation bubble. Furthermore, the size in the separation bubble with the surface roughness is much larger than the one without it. In the case under an imposition of the surface roughness, the velocity is strongly defected near the slope surface. As a result, the production of the vorticity in the separated shear layer is also inhibited, leading to the elongation in the separation bubble.
