本文選題：近場聲全息 + 非自由聲場��； 參考：《合肥工業(yè)大學》2014年博士論文

【摘要】：近場聲全息技術(shù)是一項具有強大的噪聲源識別定位及聲場可視化功能的聲學前沿技術(shù)。使用近場聲全息技術(shù)既可以重建聲源表面聲壓、法向振速等聲學量,對聲源進行識別和定位,也可以對聲源輻射的聲場進行預測,從而為機電產(chǎn)品的噪聲控制、低噪聲及聲質(zhì)量設(shè)計等提供依據(jù)。但傳統(tǒng)的近場聲全息技術(shù)對測量環(huán)境要求嚴格,即要求聲源全部位于全息面的同一側(cè)、全息面背側(cè)為自由聲場。而在實際應(yīng)用中,通常需要進行現(xiàn)場測量,并且位于全息面背側(cè)的干擾聲源常常無法移除,這就限制了近場聲全息技術(shù)的實際工程應(yīng)用。目前對于非自由聲場中的全息重建問題的解決方法通常是采用聲場分離技術(shù)作為前處理技術(shù)去除來自全息面背側(cè)的干擾聲。然而在非自由聲場中聲場由三部分組成：目標聲源在自由聲場條件下輻射的聲場(自由輻射聲場)、來自全息面背側(cè)的干擾聲(入射聲場)以及背側(cè)干擾聲經(jīng)聲源表面散射產(chǎn)生的聲場(散射聲場)。聲場分離技術(shù)只考慮了前兩種聲場,而忽略了背側(cè)干擾聲在聲源表面產(chǎn)生的散射聲場。當干擾聲源輻射強度較大時,忽略散射聲的影響會導致聲場重建失敗。 為了保證在非自由聲場中準確地重建出目標聲源輻射的聲場,需要尋求一種新的方法,能夠保證在重建過程中同時去除來自全息面背側(cè)的干擾聲和干擾聲在目標聲源表面產(chǎn)生的散射聲。本文即對這一問題展開研究。針對類平面聲源,提出了一種完全適用于非自由聲場環(huán)境的拓展的平面近場聲全息理論。針對類球形聲源,提出了一種基于球面波疊加法的自由場還原技術(shù),這一技術(shù)能夠?qū)⒛繕寺曉吹淖杂奢椛渎晥鰪氐讖臏y量的混合聲場中還原出來,為進一步進行全息重建提供自由聲場條件。為解決任意形狀聲源的聲場重建問題,將等效源法用于自由場還原,并將其用于腔體內(nèi)主動聲源的識別。最后,將質(zhì)點振速測量引入自由場還原技術(shù),提高了非自由聲場中質(zhì)點振速的重建精度。本文的主要研究工作和成果總結(jié)如下： 第一章首先簡要地回顧了近場聲全息技術(shù)的發(fā)展歷程,然后系統(tǒng)地介紹了非自由聲場中近場聲全息技術(shù)的研究現(xiàn)狀以及在應(yīng)用中存在的問題,并在此基礎(chǔ)上確定本文的研究內(nèi)容。 第二章推導出了非自由聲場中拓展的平面近場聲全息公式,將平面近場聲全息的應(yīng)用范圍拓展到了非自由聲場中。在推導過程中,將干擾聲在目標聲源表面產(chǎn)生的散射場考慮其中,保證了非自由聲場中目標聲源自由輻射聲場重建的準確性。同時對于重建公式中的奇異性問題提出了解決方法。數(shù)值仿真和實驗結(jié)果證明了該公式的有效性。 第三章提出了一種基于球面波疊加法的自由場還原技術(shù)。利用該技術(shù)可以將目標聲源在自由聲場條件下的輻射聲場從測量的混合聲場中還原出來,基于還原的聲場還可以進一步實施實現(xiàn)目標聲場的重建。另外,還提出了一種最優(yōu)球面波展開項數(shù)選取方法,為該技術(shù)的應(yīng)用提供了保障。數(shù)值仿真結(jié)果表明,利用該技術(shù)可以有效地實現(xiàn)目標聲場的還原。同時仿真中還對該技術(shù)的適用范圍進行了研究。 第四章研究了基于等效源法的自由場還原技術(shù)。首先詳細地介紹了該技術(shù)的理論,之后通過數(shù)值仿真對三種不同形狀的聲源進行分析,說明了基于等效源法的自由場還原技術(shù)對于聲源形狀具有極強的適應(yīng)性。最后將該技術(shù)用于腔體內(nèi)主動聲源的識別,仿真和實驗的結(jié)果證明了利用該技術(shù)可以在內(nèi)場環(huán)境中準確地識別主動聲源的位置。 第五章首先將質(zhì)點振速測量引入基于等效源法的聲場分離技術(shù),并且通過與基于聲壓測量和等效源法的聲場分離技術(shù)相比,證明了基于質(zhì)點振速測量和等效源法的聲場分離技術(shù)可以獲得更高的質(zhì)點振速分離精度；同時還通過仿真對影響分離精度的參數(shù)進行了分析。然后進一步推導出基于質(zhì)點振速測量和等效源法的自由場還原技術(shù)。實驗結(jié)果表明,采用質(zhì)點振速作為基于等效源法的自由場還原技術(shù)的輸入量,可以更好地實現(xiàn)目標聲源自由輻射聲場的重建。 第六章對全文的研究工作進行了總結(jié),提出了需要進一步研究的問題。
[Abstract]:In the field of non - free sound field , the sound field ( free radiated sound field ) radiated from the back side of the holographic surface and the sound field ( scattered sound field ) from the back side of the holographic surface can be removed .

In order to ensure that the sound field radiated by the target sound source can be accurately reconstructed in the non - free sound field , a new method is needed to ensure the simultaneous removal of the interference sound from the back side of the holographic surface and the scattered sound generated by the interference sound on the surface of the target sound source during the reconstruction process .

In the first chapter , the development course of near - field acoustic holography is briefly reviewed , then the research status of near - field acoustic holography in the non - free sound field and the problems existing in the application are introduced .

In the second chapter , the planar near - field acoustic holography formula is derived , and the application range of the planar near - field acoustic holography is extended to the non - free sound field . In the derivation process , the scattering field generated by the interference sound on the surface of the target sound source is considered , and the accuracy of the free radiated sound field reconstruction of the target sound source in the non - free sound field is ensured .

In chapter 3 , a free - field reduction technique based on spherical wave superposition method is proposed . It can be used to restore the radiated sound field of the target sound source under the free sound field from the measured mixed sound field . Based on the restored sound field , the reconstruction of the target sound field can be further implemented . The numerical simulation results show that the method can effectively reduce the target sound field . At the same time , the application scope of the technique is also studied .

In chapter 4 , the free - field reduction technology based on the equivalent source method is studied . Firstly , the theory of the technique is introduced in detail . Then , three different shapes of the sound source are analyzed by numerical simulation , which shows that the free - field reduction technique based on the equivalent source method has very strong adaptability to the shape of the sound source . Finally , the technology can be used in the identification , simulation and experiment of the active sound source in the cavity . The position of the active sound source can be accurately recognized in the inner field environment .

The fifth chapter introduces the technique of acoustic field separation based on the equivalent source method , and proves that the sound field separation technology based on the mass point vibration velocity measurement and the equivalent source method can obtain higher particle vibration speed separation precision compared with the sound field separation technique based on the sound pressure measurement and the equivalent source method .
At the same time , the parameters affecting the separation precision are analyzed by simulation . The free - field reduction technique based on the particle vibration velocity measurement and the equivalent source method is further derived . The experimental results show that the free - field reduction technique based on the equivalent source method is adopted as the input quantity of the free - field reduction technology based on the equivalent source method , and the reconstruction of the free - field sound field of the target sound source can be better realized .

The sixth chapter summarizes the research work of the whole text , and puts forward some problems which need to be further studied .
【學位授予單位】：合肥工業(yè)大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：TB535

【參考文獻】

相關(guān)期刊論文 前10條

1 畢傳興;唐琦;張永斌;賀春東;;雙面Patch近場聲全息實驗研究[J];合肥工業(yè)大學學報(自然科學版);2011年03期

2 ;Reconstruction and prediction of multi-source acoustic field with the distributed source boundary point method based nearfield acoustic holography[J];Science in China(Series E:Technological Sciences);2004年02期

3 畢傳興,陳劍,陳心昭;基于分布源邊界點法的多源聲場全息重建和預測理論研究[J];中國科學E輯:技術(shù)科學;2004年01期

4 于飛,陳劍,李衛(wèi)兵,陳心昭;一種穩(wěn)健的全波數(shù)聲場重構(gòu)技術(shù)[J];中國科學E輯:工程科學 材料科學;2004年09期

5 畢傳興,陳心昭,陳劍,周蓉;基于等效源法的近場聲全息技術(shù)[J];中國科學E輯:工程科學 材料科學;2005年05期

6 李衛(wèi)兵;廉美轉(zhuǎn);畢傳興;陳劍;陳心昭;;球坐標系下入射與散射聲場分離理論[J];中國科學(E輯:技術(shù)科學);2007年01期

7 畢傳興;陳心昭;徐亮;陳劍;;基于等效源法的Patch近場聲全息[J];中國科學(E輯:技術(shù)科學);2007年09期

8 畢傳興,陳劍,周廣林,陳心昭;分布源邊界點法在聲場全息重建和預測中的應(yīng)用[J];機械工程學報;2003年08期

9 于飛,陳心昭,陳劍;單全息面分離聲場技術(shù)及其在聲全息中的應(yīng)用[J];機械工程學報;2004年02期

10 徐亮;畢傳興;陳劍;陳心昭;;基于波數(shù)域外推方法的近場聲全息[J];機械工程學報;2007年09期

相關(guān)博士學位論文 前1條

1 張永斌;基于等效源法和質(zhì)點振速測量的近場聲全息技術(shù)[D];合肥工業(yè)大學;2010年

，

本文編號：1907623