电动水上飞机低噪声螺旋桨翼型优化

为降低翼型的气动噪声，以某型电动水上飞机螺旋桨所使用的RAF-6翼型为研究对象，首先通过CFD/FW-H方法计算得到翼型的升、阻力系数以及气动噪声；其次使用型函数线性叠加描述翼型的几何形状；进而，为使翼型获得设计状态下较好的声学与气动性能，由翼型的气动噪声与升阻比构成优化目标，以型函数系数为变量，以保证翼型升、阻力系数变化不超过10%为约束，使用引入响应面模型的遗传算法对翼型进行降噪优化。通过优化翼型与基准翼型的对比可知，设计状态的优化翼型气动噪声声压级降低了2.17 dB，升阻比提高1.12%，且优化翼型在小攻角状态下具有较为优异的声学与气动性能。优化结果表明，该优化方法具有一定应用价值，可为螺旋桨噪声控制研究提供参考。

Aerofoil optimization of low noise propeller for electric seaplane

Taking the RAF-6 airfoil, which is used by an electric seaplane, as the research object. Firstly, the lift and drag coefficient and aerodynamic noise of the two-dimensional airfoil were calculated by CFD/FW-H method. Secondly, linear superposition of shape function is used to describe the geometry of the airfoil. Furthermore, an aerodynamic noise optimization was conducted by using genetic algorithm applied with response surface model. The optimization takes the coefficient of shape function as the variable, the minimum aerodynamic noise of the airfoil as the optimization objective, and the aerodynamic performance of the airfoil as the constraint. The comparision between the optimized airfoil and the original airfoil shows that on the premise of ensuring the aerodynamic performance of the optimized airfoil, the sound pressure level of the optimized airfoil is reduced by 2.17dB, and the noise is significantly reduced in all frequencies and directions.