H-VAWT设计参数对其叶尖损失的影响

Affection of designing parameters to the tip loss of H-VAWT

摘要:

为了探讨在H-VAWT叶片上增加叶尖小翼或增大展弦比对风力机整体气动性能的作用和影响，计算和分析研究了不同设计参数对其叶尖损失的影响.首先以有限展长H-VAWT的气动性能为基准，将无限展长H-VAWT与之相比较所得到的气动性能的相对差值来分析设计参数—实度和翼型对其所生成的H-VAWT叶尖损失的影响，又通过比较不同展弦比所生成的H-VAWT的气动性能，分析总结了展弦比对H-VAWT叶尖损失改进的效果.结果表明：无论生成H-VAWT的设计参数(实度和翼型)如何，当H-VAWT工作在较高尖速比下(λ≥1.60)，更适合使用改善叶尖损失的措施来改善H-VAWT的气动性能；当H-VAWT实度比较大(σ≥0.96)或生成H-VAWT的翼型较厚时，有必要增加叶尖小翼或加大叶片展弦比来减少叶尖损失的不利影响，改善H-VAWT气动性能；加大叶片展弦比对H-VAWT气动性能的改善是有限的，基于设计要求及其他几何参数的限制，H-VAWT展弦比在5 ≤μ≤20范围内较合适.

Abstract:

To investigate the effect of adding the winglet or enlarging the aspect ratio of the blades to the aerodynamic performance of H-VAWT, it calculated and analyzed the impaction of different designing parameters of H-VAWT to the tip loss. It based on the aerodynamic performance of the finite blade length H-VAWT, the aerodynamic performance of the related infinite blade length H-VAWT was compared with it, the related difference of aerodynamic performance got through comparing the related difference of the aerodynamic performance, the affection of different designing parameters-solidity and airfoil to the tip loss of H-VAWT was analyzed. By means of comparing the aerodynamic performance of H-VAWTs generated by different aspect ratios, the improving effect of the aspect ratio to the tip loss of H-VAWT was analyzed and concluded. The total results illustrated that: no matter how the solidity of the H-VAWT and the airfoil adopted of the H-VAWT blade was, when H-VAWT worked at high tip speed ratios(λ≥1.60), it was necessary to adopt the measures that decreasing the adverse affection of tip loss to improve the aerodynamic performance of H-VAWT; when H-VAWT had large solidity(σ≥0.96) or adopted thick airfoils, it was also necessary to add wing let or enlarge the aspect ratio of the blade to decrease the adverse affection of the tip loss; the effect of enlarging the aspect ratio to improve the aerodynamic performance of H-VAWT was finite, based on the designing requirements and the other geometry parameters' limitation, the value of aspect ratio was suitable at 5≤μ≤20.