新型水平轴螺旋风力机气动性能分析

Aerodynamic performance analysis of new horizontal-axis spiral wind turbines

为了拓展水平轴风力机的适用范围,采用计算流体力学对2种具有不同旋叶倾角的新型水平轴螺旋风力机及其加装导管后的气动性能进行了三维数值模拟研究.结果表明:相比定角螺旋风力机,变角螺旋风力机在较小尖速比(TSR)时具有更大的功率系数(C_(P));同时,变角螺旋风力机在全TSR范围内具有更小的推力系数(C_(T)),且2种螺旋风力机C_(T)的差异随着TSR的增大而增大;2种螺旋风力机运行时高压区主要集中在轮毂前端、一阶和二阶旋叶的迎风端,低压区主要集中在三阶旋叶的背风端和轮毂后端;变角螺旋风力机前端旋叶的阻塞度相对较低,使其尾流恢复比定角螺旋风力机快;此外,导管可以显著增大2种螺旋风力机的C_(P)和C_(T),并拓宽C_(P)的TSR范围.研究结果揭示了水平轴螺旋风力机的气动特点,为该型风力机的优化设计和推广应用提供了一定的参考依据.

In order to expand the application scope of horizontal-axis wind turbines,the aerodynamic performance of the two new horizontal-axis spiral wind turbines and their ducted types are investigated by three-dimensional computational fluid dynamics simulation.The results show that the variable-angle spiral wind turbine has a higher power coefficient(C_(P))than the constant-angle spiral wind turbine in the lower tip-speed ratio(TSR)range.Moreover,the variable-angle spiral wind turbine has a lower thrust coefficient(C_(T))across the whole TSR range compared to the constant-angle spiral wind turbine,with the difference in C_(T) between the two spiral wind turbines increases as TSR grows.The high-pressure areas of the two spiral wind turbines mainly concentrate at the front of the hub,the windward side of first-order,and second-order rotating blades.Conversely,the low-pressure areas mainly gather at the leeward side of third-order rotating blades and the hub’s rear end.The wake recovery of the variable angle spiral wind turbine is faster than that of the fixed angle spiral wind turbine due to the blockage degree of the front rotating blade is relatively small.In addition,the duct can significantly improve C_(P) and C_(T) of the two spiral wind turbines,widening the TSR range of C_(P).The results reveal the aerodynamic performance of horizontal-axis spiral wind turbines,providing valuable references for the optimizing the design and promoting the application of this type of wind turbines.