A study of homogeneous and stratified flow past hills

• Main Authors: Kuo,Kuan-Huei, 郭光輝
• Other Authors: Chu,Chin-Chou;Chang,Chien-Cheng
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/13728227413841589145

博士 === 國立臺灣大學 === 應用力學研究所 === 84 === A joint numerical and experimental study of a uniform incoming flow past a hill or twin hills has been invetigated. The finite difference method is used in the numerical study. The experimental work are conducted in a towing tank and an unsteady wind tunnel. This study mainly includes three topics: 1.A homogeneous and stratified flow past a two dimensional hill. 2.A homogeneous and stratified flow past two dimensional twin hills. 3.A homogeneous and stratified flow past a three dimensional hill. The second topic of three topics opens the study of airflow past a group of hills. The present study for flows past a group of hills is more toward to the practical application because a group of hills and a basin topography exist everywhere in nature. Due to the disturbance of the topography, the flow are very complicated in windward, leeward and vally regions when the incoming flow encounters a hill- shaped obstacle. The numerical simulation is mainly used to analyze the complicated flow and to investigate the important differences between homogeneous and stratified flows. The experimental results in homogeneous flows can be used not only to analyze qualitatively the flow phenomena but also to validate the numerical simulation. In addition, the connection between the flow structures and drag forces exerted on the hill are also revealed by numerical simulation. Furthermore, the two dimensional numerical simulation are also examined by another numerical method.