一种可用于机翼优化设计中的气动噪声预测模型

发展了一种可用于翼型/机翼外形设计中的气动噪声快速预测方法。相较于传统的半经验噪声预测方法,该方法以两方程非线性k-ε湍流模型模化雷诺应力的雷诺平均方程为背景,考虑了升力系数、三维流动效应以及机翼几何参数等因素对后缘噪声的影响。而相对于直接数值模拟或声类比拟方法,该方法虽不能准确预测噪声强度,但其计算量小,能给出不同翼型/机翼的相对总声压级,以及总声压级随升力系数的变化情况,易于应用于翼型/机翼气动外形优化设计中。通过计算分析二维NACA0012翼型几何参数或来流状态的改变所带来的气动噪声差异,与ANOPP软件及Brooks等计算结果进行对比,验证了该模型的可靠性。最后,计算分析二维、三维翼型/机翼气动噪声,凸显该方法在翼型/机翼气动外形优化设计中的应用价值。

A new aerodynamic noise model for aerodynamic optimization design

A rapid prediction method of the aerodynamic noise is developed, which can be applied to the aerodynamic optimization design of the wing or airfoil.The method uses Reynolds-averaged Navier-Stokes equation with a two-equation turbulence model to include the effects of the lift coefficient, flow three-dimensionality, and wing design parameters on the trailing-edge noise.These effects are not considered in the existing, semi-empirical noise prediction methods.While compared to DNS or acoustic analogy method, the proposed noise metric is not the exact value of noise intensity, but it is a relative noise measure suitable for design studies.The new noise model is less expensive to the full-noise calculations done with computational aerodynamic noise methods.The total sound pressure level(SPL)of the different wings or airfoils and the change of the total SPL with the lift coefficient can be obtained by this method.It can be easily applied to the airfoil/wing.The reliability of the method is validated by calculating and analyzing the noise difference caused by the change of the geometric parameters or the free-stream conditions and comparing the results with the results obtained by the ANOPP software and the Brooks.Finally, Two-dimensional airfoils and three-dimension wing were computed to display the values of the method.