Flow simulation of hybrid lift and drag type vertical-axis wind turbines

• Main Authors: Jie-Ling Jhang, 張潔舲
• Other Authors: Ching-Hsiang Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/61404784500863313291

碩士 === 淡江大學 === 航空太空工程學系碩士班 === 103 === This thesis simulated hybrid lift and drag type vertical-axis wind turbines using CFD software, FLUENT. The governing equations were two-dimensional, unsteady, incompressible, turbulent Navier-Stokes equations. We used Pro/E to draw wind turbine models, and then employed Gambit to generate unstructured grids and set the boundary conditions. The simulations included three parts. The first part simulated drag type wind turbines. We observed the torque generating ability of drag type wind turbines. We installed deflectors to study their influence on the output torque. The results show that deflectors can increase the output torque due to the vortex generated by the deflectors. The second part simulated three-bladed and four-bladed lift type wind turbines. We studied the effects of wind turbine radius and blade chord length on the output torque. The results demonstrate that increasing the chord length increases the torque. A longer chord length increases the torque, but only up to a certain point, after that the blockage effect appears. Three-bladed wind turbines did not have blockage effect and four-bladed wind turbines do have. The third part simulated hybrid lift and drag type wind turbines. Drag type wind turbines can help reduce the starting wind speed for the turbines. Lift type wind turbines have better power generation efficiency than that of drag type. The simulation results show that hybrid wind turbines do increase the efficiency of the wind turbines.