Evaluation on Wind Characteristics around a Steep Simple Terrain in a Uniform Flow

Abstract

The purpose of this research is to construct a database of a non-stratified airflow past a steep simple terrain under an imposition of a uniform flow, and, in addition, is to do the accuracy inspection of the numerical model under development at present. This numerical model is referred to as the RIAM-COMPACT (Research Institute for Applied Mechanics, Kyushu University, Computational Prediction of Airflow over Complex Terrain), and is for the purpose of the prediction of airflow over complex terrain with several m to several km. This paper describes the experimental and numerical study of a non-stratified airflow past a two-dimensional ridge in a uniform flow as the first phase. The Reynolds number, based on the uniform flow and the height of the ridge, is about 104. Airflows around the ridge include the unsteady vortex shedding. Attention is focused on airflow characteristics in a wake region. For this purpose, the velocity components in the streamwise direction were measured with a SFP (Split-Film Probe) in the wind tunnel experiment. In addition, the flow visualization was performed by using the smoke-wire technique. Through comparison of the experimental and numerical results, they showed a good agreement. The accuracy of both of the wind tunnel experiment by the SFP and also numerical simulation by the RIAM-COMPACT were confirmed as the result.