Research on the improvement of the performance of savonius rotor based on numerical study

Conventional Savonius rotor is a “S-shaped” cross-section rotor, the power performance coefficient (CP=0.15) is rather low. This study introduces a new type-helical Savonius rotor, applies Calculation Fluid Dynamics(CFD) to analyze and improve the performance of the rotor from aspects ratio(H/D), number of blades, overlap distance and helical angle(θ). The results show the performance coefficient of an optimum rotor reaches 0.2, when rotor has two blades and H/D=6:1, e=0.3, θ=180°; The starting torque is also better than that of conventional rotor. The computation results coincide well with experimental results; this proves that the computation results are correct. Finally, it is worthy informing that the rotors with structure characteristics above mentioned have been produced.