Research On Aerodynamic Performance And Vibration Characteristic Of Wind Turbine Blade

The importance of the wind power is becoming more and more widelyrecognized, as an important tool to capture the wind,the aerodynamic performance ofa wind turbine’s blade determines its efficiency of utilize wind energy, and theblade’s structural vibration characteristics means a lot to the wind turbine’s safe andstable operation. Therefore, this paper take a10kW wind turbine’s blade as theresearch object, studied its aerodynamic performance and vibration characteristics.The main contents are as following:1. Based on the blade element momentum theory and the Wilson Methodconsidering the blade’s hub loss, the optimization model was built using MATLABsoftware, taking the maximal wind energy utilization coefficient as objective, theoptimize distribution of chord length and torsional angle along a10kW wind turbineblade’s blade radius was obtained. Combining with the airfoil data of SG6040, therotor’s aerodynamic shape was established.2. The SG6040airfoil’s aerodynamic performance data was obtained inFluent,its lift and drag coefficient matches with the one computed by XFOIL. Basedon the airfoil’s analysis, the rotor’s aerodynamic performance analysis was carried out,discussed the size of computational domain and the type and number of grid’sinfluence on the calculated results. The results show that the size of the computationaldomain had a great influence on rotor’s calculated aerodynamic performance, and asgrid grows, the rotor’s calculated power tends to increase. When the number ofpolyhedron grid is1/5or1/4of the tetrahedral grid, their calculated results are similar.Results also show that the Wilson method with blade’s hub loss considered is a goodblade aerodynamic shape design method.3. One flexible blade’s structure analysis and one-way/two-way fluid structureinteraction analysis was completed based on the Workbench platform. Under the staticcondition, the pre-stress and large deformation pre-stress’s influence on blade’smodal and vibration mode was investigated, the vibration characteristics under a windspeed of20m/s was also obtained. Results show that the pre-stress had little impact onthe blade’s modal frequency and vibration mode, while large deformation pre-stresshad a greater influence on the blade’s modal frequency and vibration mode. Theflexible blade’s two-way coupling results under20m/s wind shows that the blade’sactual vibration frequency is close to but greater than its first-order modal frequency, and it tend to increase， the blade’s vibration tends to convergence, flutter divergencenever happened.The work of this paper provides an efficient method for the blade’s aerodynamicshape design and the aerodynamic performance calculation of small wind turbine,theresults has important reference value and practical significance to the design of smallwind turbine’s blade and the safe and stable operation of small wind turbine.