低耗散格式在旋翼前飞气动噪声预测中的应用研究

A Method Based on Low Dissipation Roe Scheme and RANS Equations for Predicting BVI Noise of Helicopter Rotor in Forward Flight

旋翼气动噪声预测的关键在于提高旋翼流场的预测精度,特别是对涡流扰动的细节描述。由于中心格式具有较大的数值耗散,使用中心格式对涡的捕捉相当困难;此外Euler方程没有考虑物理粘性的影响,对旋翼的涡流扰动描述不够准确。文章首先基于嵌套网格,使用低数值耗散的Roe格式结合雷诺平均N-S方程预测旋翼近场流动,在此基础上预测远场噪声,一定程度上提高了前飞旋翼的流动预测能力,进而提高了旋翼气动噪声的预测精度。

Aim.Same as Ref.1,a previous paper by NWPU authors,we employ RANS (Reynolds averaged Navier Stokes) equations.Different from Ref.1,we employ the low dissipation Roe scheme.Section 2 of the full paper discusses how to select the grid so as to improve numerical calculations.Section 3 gives eqs.(2) through(5) to calculate the rotor flow field,including what is needed for predicting BVI(blade vortex interaction) aeroacoustic noise in forward flight.Section 4 gives eq.(6) and discusses the calculation of aeroaco...