Abstract:A rotor with eccentric structure was proposed in order to improve the performance of straight-bladed vertical axis wind turbine(SB-VAWT). Then, the self-starting capacity and output power were enhanced by increasing the effective acting radius of blade on the rotor shaft. Numerical simulations were carried out on a SB-VAWT rotor with six eccentricities, respectively. NACA0018 airfoil was used as rotor blade section profile. The starting torque and power coefficients were predicted. The effects of eccentricity on the aerodynamic performance were analyzed. The simulated results show that a proper eccentricity can diminish negative starting torque coefficient in some degrees at a few azimuth angles, resulting in a smooth torque coefficient curve. Consequently, the starting performance of SB-VAWT is improved effectively. Furthermore, a suitable eccentricity can increase the rotor output po-wer, and the maximum power coefficient can be raised as high as 12% compared with an ordinary rotor.
[1]刘希昌, 莫秋云, 李帅帅,等. 小型垂直轴风力发电机的气动噪声数值模拟与试验验证[J]. 流体机械, 2016, 44(6):11-16. LIU Xichang,MO Qiuyun,LI Shuaishuai,et al.Numerical simulation and analysis of aerodynamic noise based on small vertical axis wind turbine [J]. Fluid machinery, 2016, 44(6):11-16.(in Chinese)[2]李春曦, 李新颖, 叶学民. 垂直轴风力机结构及性能改进的研究进展[J]. 风机技术, 2013(1):67-73. LI Chunxi, LI Xinyin, YE Xuemin. Reviews on improved structure and performance of vertical axis wind turbines [J]. Compressor, blower & fan technology,2013(1): 67-73.(in Chinese)[3]杨从新, 李寿图, 王秀勇. 低风速下 H 型垂直轴风力机气动性能[J]. 排灌机械工程学报, 2014, 32(10): 888-893. YANG Congxin, LI Shoutu, WANG Xiuyong. Aerodynamic performance of H type vertical axis wind turbine under condition of low wind speed[J].Journal of drai-nage and irrigation machinery engineering, 2014, 32(10): 888-893.(in Chinese)[4]杨从新, 巫发明, 王立鹏,等. 设计参数对直叶片垂直轴风力机功率系数的影响[J]. 兰州理工大学学报, 2009, 35(5):47-50. YANG Congxin, WU Faming, WANG Lipeng, et al. Effect of design parameters on power coefficient of a straight-bladed vertical-axis wind turbine[J]. Journal of Lanzhou University of Technology, 2009, 35(5):47-50.(in Chinese)[5]徐璋, 霍玉雷, 陈勇, 等. 新型组合式垂直轴风机的优化设计与性能研究[J]. 浙江工业大学学报, 2015, 43(3): 261-264. XU Zhang, HUO Yulei, CHEN Yong, et al. Optimum design and study on the properties of a new combined type vertical axis wind turbine[J].Journal of Zhejiang University of Technology,2015, 43(3): 261-264.(in Chinese)[6]李岩,赵守阳,曲春明,等. Savonius风力机静态流场PIV可视化试验研究[J].排灌机械工程学报, 2018, 36(2): 159-165. LI Yan,ZHAO Shouyang,QU Chunming, et al. PIV visualization experiment on static flow field of Savonius wind turbine[J]. Journal of drainage and irrigation machinery engineering, 2018, 36(2): 159-165.(in Chinese)[7]曲建俊,王景元,许明伟,等.自适应风速垂直轴风力机的阻升转换特性[J].排灌机械工程学报, 2018, 36(2): 154-158. QU Jianjun,WANG Jingyuan,XU Mingwei,et al. Drag-lift conversion characteristics of vertical axis wind turbine with adapting wind speed[J]. Journal of drainage and irrigation machinery engineering, 2018, 36(2): 154-158.(in Chinese)[8]姚激, 黄剑峰, 彭明军, 等. 变攻角垂直轴风力机三维定常流场数值模拟[J]. 机械与电子, 2011(7): 21-24. YAO Ji, HUANG Jianfeng, PENG Mingjun, et al. Numerical simulation on 3D steady for different angles of attack of vertical axis wind turbine[J]. Machinery & electronics,2011(7): 21-24.(in Chinese)[9]舒超, 蔡新, 潘盼, 等. 垂直轴风力机改进翼型气动及功率特性研究[J]. 水电能源科学, 2015, 33(1): 162-165. SHU Chao, CAI Xin, PAN Pan, et al. Research on aerodynamic and power characteristic for improved airfoils of vertical axis wind turbine[J]. Water resources and power,2015, 33(1): 162-165.(in Chinese)[10]姚激, 黄剑峰, 袁伟斌, 等. 安装角变化下垂直轴风力机气动性能的研究[J]. 水电能源科学, 2012, 30(2): 148-150. YAO Ji, HUANG Jianfeng, YUAN Weibin, et al.Study on aerodynamic performance of vertical axis wind turbine with different installation angle[J]. Water resources and power, 2012, 30(2): 148-150.(in Chinese)[11]王颖达, 吴国庆, 倪佩佩, 等. 垂直轴风力机二维流场数值模拟[J]. 南通大学学报(自然科学版), 2013, 12(4): 42-46. WANG Yinda, WU Guoqing, NI Peipei, et al. Two-dimensional flow field numerical simulation for vertical axis wind turbines[J]. Journal of Nantong University(natural science edition),2013, 12(4): 42-46.(in Chinese)[12]陈亚伟. 基于Fluent轴流风叶的气动性能分析[J]. 流体机械,2016,44(10):51-54. CHEN Yawei.Aerodynamic performance analysis of axial fan based on Fluent[J]. Fluid machinery, 2016, 44(10): 51-54.(in Chinese)[13]孙海涛,熊鹰,时立攀. 螺旋桨流固耦合特性的数值模拟[J]. 江苏大学学报(自然科学版), 2015, 36(1): 23-29. SUN Haitao,XIONG Ying,SHI Lipan.Numerical simulation of fluid-structure interaction characteristics for propeller[J]. Journal of Jiangsu University(natural science edition),2015,36(1):23-29.(in Chinese)