风力机翼型表面V型脊状结构减阻特性的数值研究

Research on Drag Reduction Characteristics of Airfoils for H-type Wind Turbine With V-riblets on Surface

为提高风力机叶片的风能转化效率,改善翼型的气动特性,对风力机对称翼型NACA0012布置V型脊状表面结构,通过数值模拟的方法,基于湍流RNG k-ε模型对其减阻特性进行研究,分析改型前后阻力系数百分比、升阻比变化情况,并对脊状表面进行压差阻力与摩擦阻力的对比分析。结果表明：当风速与适当的开口尺寸s和开口间距a相匹配时与光滑翼型表面相比具有一定的减阻效果、升力增益变化明显;大尺寸的脊状结构不利于翼型的优化设计,s≤1.5mm时减阻效果明显,最大减阻率可达35%左右。该文所得结果可为工程实际中风力机叶片的减阻设计提供参考依据。

In order to improve the power efficiency of the turbine and the aerodynamic characteristics of airfoil, the drag reduction characteristics of V-riblet structure on symmetrical airfoil NACA0012 of wind turbine were numerical simulated based on RNG k-ε turbulence model. Then the percentage of drag coefficient, the change of drag ratio and the comparison between the pressure difference resistance and friction resistance of the ridged surface were investigated ulteriorly. The results are follows： Compared to the smooth surface, the riblet surface has a certain drag reduction effect when the wind velocity is matched with the appropriate opening size s and the opening spacing a, and the change of lift gain is obvious. The large size riblet structure is not conductive to the optimization design of the airfoil shape, and the drag reduction effect is obvious with riblets width s ≤ 1.5 mm, with the greatest drag reduction efficiency of about 35%. The results can provide a reference for the design of the resistance of wind turbine blade in engineering.