ABSTRACT

The conventional Savonius turbine is one of the most used rotors to convert the kinetic energy of natural water resources instead of potential energy. However, this rotor presents low efficiency. A twisted Savonius turbine was appeared which is considered most performant by twisting the blades of the conventional Savonius turbine along theirs spans. In fact, various experimental and numerical investigations were carried out to enhance the efficiency of the twisted Savonius turbine which has not been completely explored. In this study, an experimental investigation was carried out to assess the performance characteristics of a twisted Savonius turbine in an irrigation canal. In order to improve the efficiency of the Savonius turbine, three deflector designs were investigated numerically based on a CFD 3D numerical model. The peak value of the turbine power coefficient reaches 0.166 at a tip-speed ratio value of 0.78 without using a deflector upstream the turbine. Using the deflector design showing the highest efficiency, the peak value of the power coefficient was increased by 17.47%. The use of the proposed deflector is expected to provide toward a more effective employment of flowing water like tidal currents, river streams or other man-made water channels for electrical energy production in rural regions.

摘要

常规的Savonius涡轮机是最常用的转子之一，用于转换天然水资源的动能而不是势能。但是，该转子效率低。出现了扭曲的Savonius涡轮机，通过沿其跨度扭转常规Savonius涡轮机的叶片，可以认为是性能最高的涡轮机。实际上，已经进行了各种实验和数值研究以提高扭曲的Savonius涡轮机的效率，但尚未完全探索。在这项研究中，进行了一项实验研究，以评估灌溉水渠中扭曲的Savonius涡轮机的性能特征。为了提高Savonius涡轮机的效率，基于CFD 3D数值模型对三种导流板设计进行了数值研究。涡轮功率系数的峰值在叶尖速比值为0.78时达到0.166，而无需在涡轮上游使用导流板。使用显示最高效率的导流板设计，功率系数的峰值提高了17.47％。预期使用所提议的偏转器将有助于更有效地利用流动水，例如潮流，河流或其他人造水渠道，以在农村地区生产电能。