以某双发涡桨飞机为对象，采用精细化笛卡尔网格与混合RANS/LES数值模拟，结合FW-H方程的声类比方法，对某涡桨飞机的有动力降落构型和无动力降落构型（均为1/6缩比模型）开展气动噪声预测与对比研究。通过对比分析近场流动结构、机身表面压力分布与压力脉动探测数据、Lamb矢量的散度分布和远场观测点噪声数据，发现对于无动力降落构型，翼尖、襟翼侧缘、襟翼连接件、襟翼与机身连接处等位置的表面压力脉动显著强于其他区域；对于有动力降落构型，除上述区域外，在螺旋桨滑流的干扰下，发动机舱、机翼前缘和襟翼表面压力脉动明显增大。远场噪声观测数据表明，采用的噪声预测方法不仅能够准确捕捉螺旋桨旋转噪声主频，还能够清晰观测到2倍、3倍及4倍谐频。最终结果显示，有动力降落构型的螺旋桨旋转噪声幅值最大，是最主要的噪声源。有动力降落构型相比于无动力降落构型的总声压级要高20 dB左右。因此，建议针对该涡桨飞机降落构型，其降噪设计重点应放在螺旋桨降噪优化设计方面。

In this study， a hybrid method combining hybrid RANS/LES simulation on the fine Cartesian mesh and FW-H acoustic analogy is proposed for aero-acoustic prediction of two turboprop models （1/6 scaled） in the landing configuration： one is the powered model with twin propellers， and the other is the unpowered model without propeller. By comparing the near-field flow structure， data of pressure distribution and pulsation on the fuselage surface， distribution of Lamb vector divergence， and noise data at the far-field observation point， it is found that the surface pressure pulsation at the wing tip， flap side edge， wing-flap connector and fuselage-flap connection part are stronger than that at other areas in the unpowered model. In contrast， the surface pressure pulsation at the engine compartment， the wing leading edge and the flap are amplified significantly under the interference of propeller slipstream in the powered model. Far-field noise observation data show that the noise prediction method used in this paper can accurately capture not only the main frequency of propeller rotation noise， but also the 2， 3 and 4 times harmonic frequencies. The final results show that the rotation noise generated by the propellers is the main noise source with the highest amplitude. The overall sound pressure level of the powered model is 20 dB higher than that of the unpowered model. Therefore， it is suggested that the noise reduction design of this turboprop aircraft should focus on noise reduction of the propeller.