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150摩托車噪聲測(cè)量及聲源分析(本科畢業(yè)論文設(shè)計(jì)).doc

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150摩托車噪聲測(cè)量及聲源分析(本科畢業(yè)論文設(shè)計(jì)),摘 要摩托車噪聲對(duì)人們生活、工作環(huán)境的影響越來越大,控制摩托車噪聲已成為關(guān)系到人們生活、工作質(zhì)量的一件大事。而且在摩托車技術(shù)水平大幅提高后的今天,噪聲水平正逐漸成為人們?cè)u(píng)價(jià)摩托車等級(jí)水平的一個(gè)重要指標(biāo)。摩托車噪聲限值標(biāo)準(zhǔn)的日趨嚴(yán)格對(duì)噪聲控制水平的要求不斷提高,也推動(dòng)了對(duì)...
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150摩托車噪聲測(cè)量及聲源分析(本科畢業(yè)論文設(shè)計(jì))

摘    要

摩托車噪聲對(duì)人們生活、工作環(huán)境的影響越來越大,控制摩托車噪聲已成為關(guān)系到人們生活、工作質(zhì)量的一件大事。而且在摩托車技術(shù)水平大幅提高后的今天,噪聲水平正逐漸成為人們?cè)u(píng)價(jià)摩托車等級(jí)水平的一個(gè)重要指標(biāo)。摩托車噪聲限值標(biāo)準(zhǔn)的日趨嚴(yán)格對(duì)噪聲控制水平的要求不斷提高,也推動(dòng)了對(duì)噪聲控制的研究。
噪聲的聲學(xué)特性決定了摩托車噪聲主要取決于最大噪聲源噪聲大小,降低摩托車噪聲的前提是利用現(xiàn)代檢測(cè)技術(shù),準(zhǔn)確識(shí)別主要聲源的部位、頻率等特征,有針對(duì)性地采取有效措施進(jìn)行降噪。
本文通過采用聲強(qiáng)測(cè)試法分別對(duì)建設(shè)摩托150-A進(jìn)行整車加速噪聲和聲強(qiáng)測(cè)試,然后使用LMS.TESTLAB 8A軟件對(duì)實(shí)驗(yàn)數(shù)據(jù)進(jìn)行噪聲頻譜特性分析,得到以下結(jié)論:以排氣基頻為主的低頻噪聲0-500主要集中在排氣口處;中低頻500-1000主要以發(fā)動(dòng)機(jī)缸頭處和鏈條連接處為主;2000-2400共振帶為發(fā)動(dòng)機(jī)的缸頭處。對(duì)比各頻段能量百分比和各聲源的聲強(qiáng)絕對(duì)值,最需要迫切消除的聲源是排氣噪聲。


關(guān)鍵詞:摩托車,噪聲聲源識(shí)別,聲強(qiáng),頻譜分析

 


ABSTRACT

The influence to peoples' living and working environment by motorcycle noise is more and more serious, controlling of motorcycle noise has become an event which is related to the quality of peoples’ life and work. And, the motorcycle noise level has gradually become an important index of the eva luation on motor cycle as the technology of motor cycle manufacturing has increased. The standard of noise limit value has become more and more strict also promote the research of noise controlling.
Acoustic characteristics of noise decide that motor cycle noise depends mainly on the magnitude of biggest noise source, the precondition to decrease motor cycle noise is using modern measure technology, identify the location and frequency of main source and so on, then take corresponding measure to denoise
In this paper, according to Sound Intensity Measurement on JIANSHE MOTOR 150-A, then use LMS.TESTLAB 8A to take Spectrum characteristic analysis, and get the results:Low frequency noise 0-500 mostly located in exhaust port;Middle and low frequency noise 500-1000 mostly located in engine cylinder head;Resonance band 2000-2400 mostly located in the junction of chain.Comprise the energy percentage and absolute value of acoustic intensity in each frequency band, urgently need to eliminate is exhaust noise.


Keywords:Motor cycle; Recognition of noise source; sound intensity; spectrum analysis


 
 
目   錄
摘    要 I
ABSTRACT II
1緒論 1
1.1 摩托車噪聲概述 1
1.2摩托車噪聲研究背景意義 2
1.3國(guó)內(nèi)外研究現(xiàn)狀 4
1.4本文研究?jī)?nèi)容 6
2.摩托車噪聲源特性 7
2.1噪聲的度量 7
2.1.1聲壓、聲強(qiáng)、聲功率 7
2.1.2噪聲的頻譜與頻程 8
2.1.3噪聲的計(jì)權(quán)分析 9
2.2摩托車噪聲分析 9
2.2.1發(fā)動(dòng)機(jī)噪聲 9
2.2.2其他噪聲 13
2.3本章小結(jié) 13
3.摩托車噪聲源的識(shí)別方法 14
3.1常用的噪聲源識(shí)別方法 14
3.1.1主觀評(píng)價(jià)法 14
3.1.2近場(chǎng)話筒拾音法 14
3.1.3分別運(yùn)行法 15
3.1.4鉛覆蓋法 15
3.1.5頻率分析法 15
3.1.6定轉(zhuǎn)速變功率頻譜分析法 16
3.2聲強(qiáng)測(cè)量法 16
3.2.1表面聲強(qiáng)法 16
3.2.2雙傳聲器法 16
3.3本章小結(jié) 18
4建設(shè)150-A摩托車噪聲聲源識(shí)別測(cè)試 19
4.1加速噪聲測(cè)試 19
4.1.1實(shí)驗(yàn)方案 19
4.1.2 加速噪聲測(cè)試結(jié)果分析 21
4.1.3加速噪聲數(shù)據(jù)頻譜分析 22
4.1.4加速噪聲測(cè)試小結(jié) 23
4.2整車聲強(qiáng)測(cè)試 23
4.2.1實(shí)驗(yàn)方案 23
4.2.2聲強(qiáng)試驗(yàn)數(shù)據(jù)分析處理 25
4.2.3聲強(qiáng)測(cè)試小結(jié) 29
4.3本章小結(jié) 29
5全文總結(jié) 30
參 考 文 獻(xiàn) 31
致   謝 32