Experimental studies were conducted at a hemi-anechoic chamber to investigate the effectiveness of trailing-edge (TE) serration designs for reducing aerodynamic noise of a propeller. The propeller noise was measured under different speeds in both the vertical and horizontal directions. The thrust force produced by the propeller was also measured at rotational speeds. The flaplet, concave and sawtooth shapes of serration were integrated on the TE of baseline propeller to obtain three different serrated propellers. The results show that the flaplet, concave and sawtooth propellers improve the thrust force more than 10% on the basis of baseline propeller. Three types of TE serration all managed to attenuate large amount of noise, while the sawtooth serrations are more effective than flaplet and concave serrations in a wider frequency range. Then, the serration distribution length (DL) of sawtooth propeller was trimmed to other three different values to obtain the 3/4-DL, 1/2-DL and 1/4-DL propellers. The 3/4-DL propeller exhibited best comprehensive performance, by an average of 2.7 and 3.0 dB noise reduction in tested two positions and simultaneously generated overall 6.7% higher thrust force than did the baseline propeller. The morphological and parametric effects of TE serration in current studies are more significant in a relative high Reynolds number (1.4 × 10⁶).

在半消声室中进行了实验研究，以研究后缘（TE）锯齿状设计降低螺旋桨空气动力噪声的有效性。螺旋桨噪声是在垂直和水平方向上以不同速度测量的。还以旋转速度测量了螺旋桨产生的推力。将锯齿状的瓣状，凹状和锯齿状整合到基线螺旋桨的TE上，以获得三种不同的锯齿状螺旋桨。结果表明，在基线螺旋桨的基础上，襟翼，凹形和锯齿形螺旋桨可将推力提高10％以上。三种类型的TE锯齿均能减弱大量噪声，而锯齿锯齿在更宽的频率范围内比小板和凹锯齿更有效。然后，将锯齿螺旋桨的锯齿分布长度（DL）修整为其他三个不同的值，以获得3 / 4-DL，1 / 2-DL和1 / 4-DL螺旋桨。3 / 4-DL螺旋桨表现出最佳的综合性能，在测试的两个位置平均降低了2.7和3.0 dB的噪音，同时产生的总体推力比基线螺旋桨高6.7％。在相对较高的雷诺数（1.4×10）下，当前锯齿状锯齿的形态学和参数学效应更为显着。推力比基线螺旋桨高7％。在相对较高的雷诺数（1.4×10）下，当前锯齿状锯齿的形态学和参数学效应更为显着。推力比基线螺旋桨高7％。在相对较高的雷诺数（1.4×10）下，当前锯齿状锯齿的形态学和参数学效应更为显着。⁶）。