共查询到20条相似文献,搜索用时 109 毫秒
1.
工程机械机外噪声声源分析及降噪处理 总被引:1,自引:0,他引:1
某型全液压抓料机的机外噪声较大,需确定其噪声源并进行降噪处理.分别测量机外前、后、左、右4个方位噪声的声压信号并进行频谱分析,采用多方位噪声信号分析、机器工作特性和机器结构布置相结合的方法判断噪声源.结果表明,机外噪声主要由风机运转噪声和发动机排气噪声组成.根据两噪声源各自的频率特性及机器的结构布置特点,采用微穿孔板共振吸声结构作为降噪措施,分别设计并安装了消声器和隔声罩,抓料机外噪声下降了5.8 dB,达到了欧洲最新噪声限制标准的要求. 相似文献
2.
针对摩托车的噪声进行研究,分析并确定了摩托车的主要噪声及主要噪声源,进而对摩托车的排气噪声、进气噪声、机械噪声和燃烧噪声提出了相应的简易降噪措施。 相似文献
3.
4.
5.
<正> 随着汽车工业的迅猛发展,汽车噪声、排气污染和安全已成为汽车三大主要公害。发动机排气是排气污染和主要噪声源之一,要降低发动机噪声,一是降低声源噪声,二是设计性能好的排气消声器。表1是几种汽车排气消声器的性能参数。国产汽车排气消 相似文献
6.
汽车加速过程排气噪声是一种强非稳态的噪声,使用传统的频谱分析方法往往会出现"频率模糊"现象。为了了解发动机加速阶段排气噪声特性、研究发动机转速对加速过程排气噪声的影响,采用了阶次跟踪方法对某四缸发动机加速过程排气噪声进行了测试,分析了发动机加速过程排气噪声的主要阶次及主要噪声源,揭示了发动机排气噪声声压级变化与发动机转速的关系,为该发动机排气消声器的设计和优化提供了重要的参考依据。 相似文献
7.
8.
9.
本文以后置柴油机客车为对象,进行整车的远场、近场、噪声分离等多项试验,通过分析计算噪声样本的偏相干函数、噪声频谱,确定冷却风扇噪声、排气消声器噪声、发动机右侧传出噪声是该车的主要噪声源。在不改变该车主要结构的前提下,采用玻璃纤维吸声材料对发动机罩等部位进行屏蔽,加大冷却风扇直径降低风扇转速;在排气管消声器外包扎吸声材料等措施进行对比降噪试验,达到较好的整车降噪效果。 相似文献
10.
11.
12.
纺纱锭子性能的优劣对生产效率和纱线质量具有决定性的影响。以纺纱锭子运转中的噪音信号为考察对象,对纺纱锭子运转过程进行分析。利用快速独立成分分析FastICA算法对工作状态中的锭子声压信号进行噪音源数据分离分析,得到工作状态下源信号的主频率。将工作状态下源信号的主频率与锭子不运转下的噪音主频率进行对比,38.88%分离主频率与锭子不运转下的噪音主频率一致,44.44%分离主频率与锭子不运转下的噪音主频率相近,最小误差为0.05%。实验与分析结果表明,FastICA算法用于噪音源信号主频率分离的有效性和正确性。 相似文献
13.
TCM叉车消声器的试验研究 总被引:1,自引:0,他引:1
地TCM叉车消声器的消声量测试,得知其对中高频段噪声声效果不好。对该消声器进行结构参数分析,并在改进设计中增大了消声器容积比和改进排气尾管结构形式,改进后的消声器经装车试验,表明改进是成功的。 相似文献
14.
Coherence technique for noise reduction in rotary compressor 总被引:1,自引:0,他引:1
H. C. Kim M. G. Cho J. Kim J. H. Park J. Shim 《Journal of Mechanical Science and Technology》2012,26(7):2073-2076
The noise and vibration of a rotary compressor, a type of multi-input, single output system, are generally studied through frequency analysis. Although this method is effective in analyzing frequency components, using this method to identify the specific source of the noise (4 kHz to 6 kHz) is difficult. Hence, noise source should be studied systematically. In this study, a coherence analysis method based on systems analysis is used to identify the compressor noise source. Compressor noise source is identified through the coherence between the vibration signals on the shell of the compressor and the noise signal at one point near the compressor (1 m away from the compressor). A one-third octave band is employed for frequency analysis. The design of experiment is conducted to identify possible noise factors, such as volume, size, and neck area of the resonator in the compressor cylinder. Analysis showed that noise was generated from the cavity of the cylinder and the muffler inside the rotary compressor. A new type of muffler was applied to the rotary compressor to verify this finding. Noise was dramatically reduced. 相似文献
15.
16.
Jian-Hua Fang Yi-Qi Zhou Xiao-Dong Hu Li Wang 《International Journal of Precision Engineering and Manufacturing》2009,10(5):59-66
Through analyzing the harm of the exhaust noise from the excavator, this paper illuminated the importance of the noise measurement
and analysis work,. According to some correlative measurement standards, using some instruments in hand, a set of exhaust
noise measurement system especially for the excavator was designed. The exhaust engine noise from an excavator produced by
a construction machinery corporation was measured and analyzed, and then, seven mufflers with different structures were designed.
After analyzing the frequency spectrums of seven impedance mufflers of different structures respectively, we selected the
muffler j which was of best noise elimination performance among the seven mufflers. The highest noise elimination of muffler
j was up to 16.3dB, which could reduce the exhaust noise from the excavator in a larger degree. At last, we analyzed the structures
and corresponding effects of noise elimination for the seven mufflers and made some important conclusions. 相似文献
17.
对具有汽车尾气净化功能的消声器的消声性能和净化性能进行了较深入的研究。在理论上,利用矩阵变换的原理,建立了安装催化剂的双层摩擦穿孔声管的声场传递矩阵数学模型;利用已有的研究成果,推导出在考虑气流速度影响时的几种典型声学单元的声场传递矩阵;列出了排气噪声和废气含量测试结果,并进行了分析。 相似文献
18.
针对某车型怠速工况下车内噪声较大问题,采用消去法进行了噪声源排查,确定排气口辐射噪声是影响怠速车内噪声较大的主要原因.文中利用GT-Power软件建立了排气系统模型,并与实验设计方法相结合,通过调整排气系统内部管道和隔板的穿孔率,提高了排气主消声器的传递损失,最后通过制作样件对改进方案进行实车验证,整车怠速噪声达到目标要求. 相似文献
19.