Numerical Simulation of Wind Tunnel Blockage Effects on the Performance Tests of Small Horizontal-Axis Wind Turbines

• Main Authors: Yu-Hsin Lin, 林祐新
• Other Authors: Hong-Chia Lin
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/g3fd69

碩士 === 國立虎尾科技大學 === 航空與電子科技研究所 === 100 === This study uses computational fluid dynamics software FLUENT 12 to assess the performance of a 2.4 m-diameter horizontal-axis wind turbine designed for constant tip speed ratio operation in wind tunnel testing. Because the blockage effects of the tunnel wall, the acceleration of air flow may increase the wind turbine’s performance. This research investigates the blockage effects of the test section on the wind turbine performance by using a moving mesh method to simulate blade rotation and by solving unsteady, three-dimensional incompressible flow with the free stream velocity of 8 and 10 m/s to determine the relationship of power coefficient and blockage ratio under design tip speed ratio operation condition. The result shows that the blockage ratio is 10%, the power coefficient increases 7.8 % for the free stream velocity is 8 m/s, 6.8 % for the free stream velocity is 10 m/s and the blockage ratio is 20 %, the power coefficient increases 17.0 % for the free stream velocity is 10 m/s, respectively, which is close to the simple formula suggested by Pope and Harper for bluff body correction.