Optimization Design of Savonius Diffuser Blade with Moving Deflector for Hydrokınetıc Cross Flow Turbıne Rotor

Abstract

The conventional Savonius turbine is a good concept for small size wind-renewable energy systems; unfortunately always it has low efficiency. Inspired from the Savonius Blade, this research project designed the diffuser form as compartment between S blade and Tandem Blade of Savonius to produce “jet flow” through narrow gap on the advancing blade in order to rotate more powerful the returning blade. The reason to change the air (wind) by using water as working fluid is to increase the body force (BF) which works on the blade due to increasing the density of fluid. The new model of Hydrokinetic Cross Flow Vertical Axis Turbine (CROSSVAT) is developed from Savonius S rotor with using Savonius Diffuser Blade (SDB) and moving deflector (guide blade). The function of SDB is to increase the velocity ratio on narrow gap (Rcv) also the drag force on surface of blades. Research method used the CFD simulation and Response Surface Method (RSM) to optimize the geometry of tandem blade and moving deflector (the moving guide blade). This study results two model CROSSVAT rotor using Tangential Deflector (model 1) and Radial Deflector (model 2).