Abstract The present study proposed a novel porous deflector in front of the Savonius wind turbine to improve the performance. This new deflector was specifically proposed to minimize the severe effects of the complex wake zone created behind the conventional solid deflector that had not been investigated yet. This caused a deeper investigation into the effect of severe negative effects on the turbine performance to achieve an appropriate design configuration. Therefore, different configuration parameters were taken into account during the numerical process. The unsteady Reynolds-averaged Navier-Stokes equation in conjunction with the SST k-ω turbulence model was numerically solved. Comprehensive comparisons of torque, power, and flow structures between deflector configurations and the standard Savonius turbine were performed to illustrate the mechanism of how the porous deflector improved the turbine performance. Using a porous deflector caused the wind flow passed through the porous zone resulted in a breakdown of the wake zone behind the deflector. Thereby, the flow structures became more regular with fewer fluctuations. The results demonstrated that there is an appropriate porosity value to obtain the highest torque and power coefficients. The maximum value of the power coefficient increased by approximately 10% using the favorable configuration of porous deflector at a tip speed ratio of 1. The notable observation was that the appropriate configuration increased the static torque coefficient approximately 2 times in the rotation angles between 0° and 30° which proved the self-starting ability besides power coefficient enhancement.

中文翻译：

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使用多孔导流板的 Savonius 垂直轴风力涡轮机的性能改进

摘要 本研究在Savonius 风力涡轮机前提出了一种新型多孔导流板以提高其性能。这种新的偏转器是专门为最大限度地减少在尚未研究的传统固体偏转器后面产生的复杂尾流区的严重影响而设计的。这导致对涡轮机性能的严重负面影响的影响进行更深入的研究，以实现适当的设计配置。因此，在数值过程中考虑了不同的配置参数。非定常雷诺平均 Navier-Stokes 方程结合 SST k-ω 湍流模型进行了数值求解。扭矩、功率、执行导流板配置和标准 Savonius 涡轮机之间的流动结构和流动结构，以说明多孔导流板如何提高涡轮机性能的机制。使用多孔导流板导致通过多孔区的风流导致导流板后面的尾流区破裂。因此，流动结构变得更加规律，波动更少。结果表明，存在适当的孔隙率值以获得最高的扭矩和功率系数。在叶尖速度比为 1 时，使用多孔偏转器的有利配置，功率系数的最大值增加了约 10%。