通过对运行状态下装有降噪弹性车轮的100%低地板车和装有普通钢轮的B型地铁的车轮近场噪声试验分析,得到实际运行状态下降噪弹性车轮的频谱特性,也获得降噪弹性车轮(下称弹性车轮)相对于普通钢轮的降噪特性的差别。研究结果表明,与普通钢轮相比,弹性车轮的近场声辐射较小。当车速为60 km/h时,车轮内侧距离车轮30 cm处实测噪声水平测试结果分析表明,同一位置弹性车轮近场声辐射比普通钢轮降低2.4 d BA。在该位置,弹性车轮在较宽的频域范围内有较好的降噪效果,但是在低频和1 000 Hz~1 600 Hz频率区段内降噪较薄弱,这主要是由弹性车轮自身的固有振动特性造成的。相关分析结果可为弹性车轮进一步降低噪声提供参考。
The near field noises of resilient wheels and plain steel wheels of the full low-floor train were tested respectively. The noise reduction characteristics of the two kinds of wheels in operation condition were obtained and compared. The results show that compared with the plain steel wheel, the noise reduction effect of the resilient wheel is obvious. The noise reduction can reach 2.4 d B(A) at 60 km/h traveling speed. The resilient wheel has good noise reduction effect in a quite wide frequency range, but its noise reduction effect is low in the low frequency range and in the range of1 000 Hz-1 600 Hz. This is mainly due to the inherent vibration characteristics of the resilient wheel. This analysis may provide a reference for noise reduction design of the resilient wheels.