Today, fuzzy modeling has found various applications. Fuzzy modeling has been used to model of wind turbine performance based on power ratio. In this research, the experimental data are collected over many prototype vertical Savonius rotors. The Reynolds number has negligible effect in power ratio. Therefore, input and output quantities for the prediction in fuzzy inference system are the tip speed ratio (TSR) and power ratio, respectively. In addition, fuzzy output was constructed in order to predict power factor from the limited number of accessible experimental data. The results reveal that there is an excellent agreement between the experimental data and predicted values. The simulation has the capability of providing reasonable predictions for the maximum power of rotors and maximizing the efficiency of Savonius wind turbine.

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