消隙齿轮降低柴油机怠速噪声的应用研究  

Application on reducing idle noise of diesel engine by using anti-backlash gear

作　　者：李民[1] 陈烨龙 庞建武[2] 杜慧勇[1] 徐斌[1] Li Min Chen Yelong Pang Jianwu Du Huiyong Xu Bin(Vehicle ＆ Transportation Engineering School, Henan University of Science and Technology, Luoyang 471003, China Guangxi Yuchai Diesel Engine Co., LTD, Yulin 537005, China)

机构地区：[1]河南科技大学车辆与交通工程学院,洛阳471003 [2]广西玉柴机器股份有限公司,玉林537005

出　　处：《农业工程学报》2017年第1期63-69,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家重点研发计划项目(2016YFD0700701)

摘　　要：柴油机噪声影响着农业机械操作者的身心健康,该文为了解决某型柴油机在怠速工况下的异响噪声问题,采用仿真与试验相结合的方法进行研究。首先,通过声强和声压测试确定了噪声的主要产生部位;然后,基于Hypermesh和Abaqus软件建立了曲轴及整机零部件的有限元模型,并通过模态试验验证了有限元模型的准确性,基于Excite软件建立了配气正时传动系统和整机的多体动力学模型,发动机整机振动计算时考虑了缸内燃气压力、正时系统及配气机构全阀系激励和活塞敲击激励。多体动力学仿真结果表明:齿轮的反向敲击出现时,齿轮工作面的接触力消失,进排气齿轮在背隙侧发生接触产生冲击力,进而造成发动机在怠速时产生"哒哒"的异响噪声;整机振动仿真结果表明:使用消隙齿轮可以消除进/排气凸轮轴齿轮的反向敲击,在1 000~2 500 Hz范围内,使得齿轮室盖和缸盖罩的振动速度级降低了7 d B左右。最后在半消声室的发动机台架上,对有无消隙齿轮的柴油机进行了振动加速度、噪声和声品质的对比试验,试验表明:怠速工况下,使用消隙齿轮后,前端发出的"哒哒"异响噪声消失,齿轮室盖振动降幅很大,前端1 m噪声声压级降低了5~9 d B(A),声品质也有了明显改善。因此,当内燃机其它齿轮传动部位出现齿轮反向敲击声时,可考虑使用消隙齿轮予以解决。Dieselengine noise has a bad influence on physical and mental health of agricultural machinery operators. In this paper, we aimed at eliminating the abnormal rattling noise of a diesel engine running at idle speed condition by simulation and experiment. Firstly, on engine test bench in a semi-anechoic room, the rattling noise was identified through sound intensity and sound pressure measurement, the nine point sound pressure results showed that the rattling noise was more obvious in front of the engine, and the sound intensity of the engine front part showed that the main part of rattling noise was generated from the timing gear cover in front of intake camshaft and exhaust camshaft. In order to eliminating the abnormal rattling noise, some improvements were also attempted, such as using acoustic shield over intake camshaft and exhaust camshaft, improving the accuracy of timing gears through gear grinding, optimizing the parameters of valve-chain hydraulic tension device, replacing new timing chain, but the experiments showed all these improvements had no effect in noise reduction. Through analyzing of the previous experimental results, a hypothesis was proposed that the idle abnormal noise might be caused by the knock between the intake cam gear and exhaust cam gear, thus replacing intake cam normal gear by anti-backlash gear might eliminating the gear knock, and the diesel abnormal idle noise might be solved. Secondly, in order to identify if the gears knock really happened, multi-body dynamic simulation was performed. By using Hypermesh and Abaqus software, the FEM（finite element modeling） model of the engine including crankshaft, cylinder block, cylinder head and other engine components were built, and the model tests of each part were performed. The results showed that the frequency difference between experiment and simulation was within 10%, the accuracy of the FEM model was acceptable. By using Excite software, the multi-body dynamics model including the gear of the intake camshaft were built separatel

关 键 词：柴油机 振动 齿轮 怠速工况 消隙齿轮 噪声 

分 类 号：TK42[动力工程及工程热物理—动力机械及工程]