Study on the performance of a three-dimensional jet-flapped foil in the periodical swing of the jet deflection angle

• Main Author: 余家齊
• Other Authors: 吳聰能
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/43168295324949283446

碩士 === 國立臺灣大學 === 造船及海洋工程學研究所 === 88 === The purpose of this paper is to study the hydrodynamic performance of a three dimensional jet-flapped foil in unsteady motion by using the panel method. The unsteady motion is the periodical swing of jet deflection angle. A velocity-based panel method consists of distributing the sources on the wing surface and the bound vortex ring on the mean camber surface. During unsteady motion, the wake vortex rings are shed from the trailing edge to simulate the wake of the flow field. Under satisfying the boundary conditions including the flow tangent condition on the wing surface and the jet condition at the trailing edge, the program will be constructed. Through the present study, the following conclusions can be obtained: The periodical swing of jet deflection angle will generate the delay effect in the flow field. For higher swing frequency, the phase lag of lift coefficient curve is more obvious.