Design Andaerodynamic Noise Study Of Large Scale Wind Turbine Blade

As a type of renewable energy, wind energy has great development and utilizationvalue. The wind power industry has been developing rapidly in recent years in China, andwind power has become the third largest energy. However, the noise pollution problemcaused by wind turbines is restricting the development of wind power industry. With windturbines becoming more and more large, the aerodynamic noise emitted by the wind turbinehas a more and more serious impact on the residents around the wind farm. So it is verynecessary to study the source of aerodynamic noise and propagation characteristic for thepurpose of reducing it.Based on the1.5MW horizontal axis wind turbine blade, the main works conducted inthis paper are as follows.(1) The Glauert model for blade design is introduced, and the geometric parameters of1.5MW horizontal axis wind turbine blade such as the chord length and the setting angle ofevery blade section are calculated.(2) Three-dimensional solid model of the blade is established using the softwareSOLIDWORKS. And the flow field around a single blade is simulated using the fluidanalysis software FLUENT. The output power of the designed turbine is checked to ensurethe designed blade can meet the aerodynamic performance requirements.(3) The main components of the aerodynamic noise caused by wind turbine areintroduced. The vortex noise around the airfoil is simulated via the method that combinesLarge Eddy Simulation (LES) and Lighthill acoustic analogy. Firstly, the flow field aroundthe symmetric airfoil NACA0018is got using the LES. Then the information of the flowfield is extracted by the software ACTRAN. And the sound field is simulated with themethod of Lighthill acoustic analogy. The numerical results like the aerodynamic charactersand the turbulent vortex distribution are compared with that in the references.(4) The vortex noise around the radial blade section is simulated with the methodmentioned above. The position of the vortex noise source and its propagation character areobtained. The effect of the relative inflow velocity and the attack angel on the vortex noiseis studied as well.