eng Science and Education Publishing Sustainable Energy 2014-07-02 2 4 121 125 10.12691/rse-2-4-1 RSE2014241 article Ibrahim Mabrouki 1 Zied Driss zied.driss@enis.rnu.tn 1 Mohamed Salah Abid 1 Laboratory of Electro-Mechanic Systems (LASEM), National School of Engineers of Sfax (ENIS), University of Sfax, B.P. 1173, Road Soukra km 3.5, 3038 Sfax, TUNISIA The water Savonius rotor is classified as a vertical axis water rotor like the Darrieus, Gyromill or H-rotor. The advancing blade with concave side facing the water flow would experience more drag force than the returning blade, thus forcing the rotor to rotate. In this work, we are interested on the study of the of the internal overlap effect of a water Savonius rotor. The experimental results is developed using a hydraulic test bench. The test bench consists on an intake, a control gate, a penstock, a canalization, a test section, an outflow and a pump. A detailed description of the global characteristics is presented such as power, dynamic torque, power and its coefficients. http://pubs.sciepub.com/rse/2/4/1/rse-2-4-1.pdf Savonius rotor internal overlap hydraulic test bench power coefficient torque coefficient