Study On Optimal Design Of Main Parameters For Blades Of Savonius Wind Turbine

With the progress of the society, the energy demand in the world has been increasing,but the to tal of the energy is limited after all and the energys to rage capacity can not meet the growing energy needs one day in the long run.So the energy crisisis the most important problem that we need to solve. In view of the current situation of the energy structure of our country, it is imperative to develop the clean energy.The horizon talaxiswind turbine which relieson the advantage of highro to rpower efficiency occupies the main market position.But the difficulty in startinga slow windvelocity and the deficiency of the anti-compression ability in the bladesas high winds peedare the factors which would restrict the development of the horizon talaxis wind turbine.However, the verticalaxis wind turbine has low rotor power efficiency,but it has the advantages of structural stability and good starting performance, which draw people’s broad attention.In this paper, the study of experiments and numerical simulation for the main parameters of the blades of the wind turbine of Savonius for the aerodynamicper for mance of the wind turbine has been developed,in order to optimize the camber the wind turbine of Savonius.Basedon the low speed windtunnel of B1/K2 of Inner Mongolia University of Technology, the experiment alplat form of the wind tunnel measurement is built to test the blade surface pressure.The blade surface pressure of multiple groups from different angle sistested according to the synchronization pressure measurement technology of multiple points. In addition to the characteristic such as the ratio of height to diameter and the overlapratio,a new optimal parameter called camberisin troducedin this paper.This parameteris proposed under the basis of the wing the ory.The camber of ratiois definedas the maximum vertical distance between the arcto the chord and in the airfoil.According to analyze the over lapratio, the ratio of height to diameter and the camber for the wind turbine of Savonius, the result shows that the per for mance of the testing blades turns to be best when the over lapratiois0.2in these three types of 0.2、0.3、0.4, the ratio of height to diameter is4in these three types of 2、3、4 and the camberis0.3in these three types of 0.3、0.4、0.5.Then according to the conclusion of the experiments, the study of numerical simulationiscarriedout to analyze the influence of the parameters of the camber morenotably.According to use the method of the Computational Fluid Dynamics(CFD),six types of the camber the wind turbine of Savonius has been studied under the method of the numerical simulation.Six types of the camberare0.25、0.3、0.35、0.4、0.45、0.5.According to analyze the numerical simulation results of to rque, the influence of the rotor power efficiency for the camberi sobtained which is fitted asonepolynomial and the extreme value is found.The result shows that the highest rotor power efficiency appears when the camber of the wind turbine of Savoniusis 0.3614.From the velocity and pressure distribution which is gottenis the numerical simulation; the influence mechanism of the wind turbine of Savoniuscan beanalyzed.The results show that decreasing the camber can reduce the obstruction of the effect of airflow, which leads the flowveloc it y of leeside to increase and the pressure to decrease.This increases the highest moment coefficient and the dragco efficient of the blades, and can make the center of pressure position of the blades move to the external of the impellers, which achieve the purpose of improve the performance of the wind turbine of Savonius.According to experiments and numerical simulation, the influence of the wind turbine of Savonius with the over lap ratio, the ratio of height to diameter and the camber for have been found, and the optimum camberis determined, which provide the the oretical basis for the optimization of the wind turbine of Savonius.