Numerical simulation of starting performance of vertical axis wind turbine with B-Spline curve wind gathering devices
LI YAN1,2*, MA Yunfei1, TONG Guoqiang1, YANG Shengbing1, XIAO Zhenjun1
1. College of Engineering, Northeast Agricultural University, Harbin, Heilongjiang 150030, China; 2. Heilongjiang Provincial Laboratory of Technology and Equipment for Agricultural Renewable Resource in Cold Region, Harbin, Heilongjiang 150030, China
Abstract：In order to further improve the static start-up performance of straight-bladed vertical axis wind turbines(SB-VAWT), a wind gathering device(WGD)with convex streamline profile was proposed based on the B-spline curve generation method. It was installed at the top and bottom of the wind wheel respectively to improve the incoming wind flow velocity near the wind turbine, make the wind wheel to absorb more wind energy and achieve the characteristics of easier start-up. Five design structural parameters were selected for the WGD including: the clearance distance between WGD and wind turbine ΔL, Bottom circle radius R1, top circle radius R2, entrance angle α1 and outlet angle α2. The design method adopts a quadratic rotation orthogonal combination to screen the optimal model. The influence of WGD parameters on the static starting performance of SB-VAWT was studied through three-dimensional numerical simulation, and the optimal combination of shape parameters was obtained. In addition, a static three-dimensional numerical simulation of SB-VAWT with or without WGD was carried out. The results show that the static starting performance of SB-VAWT is significantly improved by adding WGD with convex streamline profile. The starting performance of a SB-VAWT has been significantly improved. Under low wind speeds, the performance improvement is more significant. The WGD can increase the average starting torque coefficient of SB-VAWT by a maximum of 38.8%, and the peak average starting torque coefficient can be increased by a maximum of 31.2%.
