報告題目:Kinematics and Aerodynamics: Deep Dynamic Stall in Heaving and Pitching Airfoil
報告人:Kyung Chun Kim(Pusan National University 國立釜山大學)
報告時間:2017年9月14日 下午3:00
報告地點:C12号樓619會議室
主辦單位: 國際合作交流處、科協、航空宇航學院
報告人簡介:Kyung Chun Kim博士是韓國國家工程院院士,韓國流動顯示技術協會主席,在韓國國立釜山大學與國際多所大學擔任過教學與研究工作。他長期從事流動可視化相關問題的研究,是2010年在韓國大邱舉行的第14屆國際流動可視化研讨會的主席。第12屆國際粒子影像測量學研讨會的主席。先後發表學術論文570餘篇,是《Journal of Visualization 》、《 Journal of Flow Visualization and Image Processing》雜志主編。
報告内容簡介Kinematics changes flow characteristics substantially. This talk presents deep dynamic stall behavior under heaving and pitching motions of NACA0012 airfoil. The effective angle of attack is the same for both motion. Large Eddy Simulation has conducted to find 3D flow structures and aerodynamic properties. The Reynolds number used in this study (Re=135,000) is in the same order of magnitude as those for medium and small size wind turbines, but is at least one order of magnitude lower than those for the large-scale wind turbines. The thickness of domain (foil span) is selected one chord length. The outer boundaries are selected based on the above descriptions far away enough to neglect blockage effect. The total number of nodes for the final design is 2.9×106 and 500 nodes are placed along the foil and are clustered close to the leading and trailing edges. It is shown that the flow pattern in boundary layer and wake zone will change if the kinematic of airfoil switches from pure heaving to pure pitching. Additionally, some significant differences between aerodynamic loads are observed for aforementioned kinematics. Particle image velocimetry measurements were carried out to validate the CFD results for lower Reynolds number cases (Re=90,000 and 15,000). It is found that Reynolds number effect is closely related to the formation of 3D vortex structures.