車輛聲學(xué)包開發(fā)技術(shù)設(shè)計與優(yōu)化綜合

1、第1頁材料、設(shè)計及優(yōu)化車輛聲學(xué)包開發(fā)技術(shù)第2頁Part1 聲學(xué)包開發(fā)的意義Part2 聲學(xué)包開發(fā)的內(nèi)容Part3 聲學(xué)材料性能測試方法Part4 聲學(xué)包開發(fā) CAE 方法Part5 應(yīng)用開發(fā)實例匯報內(nèi)容第3頁聲學(xué)包開發(fā)意義Part 1第4頁聲學(xué)包開發(fā)意義路面/底盤噪聲源動力傳動系噪聲源Structure-borne NoiseAirborne Noise傳動系統(tǒng)經(jīng)過車身/底盤傳輸路面/底盤經(jīng)過車身傳輸Wind noise第5頁聲學(xué)包開發(fā)意義路面/底盤噪聲源動力傳動系噪聲源Structure-borne NoiseAirborne Noise傳動系統(tǒng)經(jīng)過車身/底盤傳輸路面/底盤經(jīng)過車身傳輸Win

2、d noise聲學(xué)包處理方案第6頁聲學(xué)包開發(fā)意義Noise PerformanceCostWeightSpaceA balanced Solution第7頁聲學(xué)包開發(fā)內(nèi)容Part2第8頁整車NVH開發(fā)流指標(biāo)設(shè)定/分解標(biāo)桿研究NVHCAE/DVP驗證樣車調(diào)校第9頁聲學(xué)包開發(fā)流程指標(biāo)設(shè)定/分解標(biāo)桿研究NVHCAE/DVP驗證樣車調(diào)校聲學(xué)包指標(biāo)設(shè)定及分解地板/車門等TL地毯傳遞損失中控臺傳遞損失發(fā)動機艙/乘客艙吸聲系數(shù)艙蓋吸聲性能頂襯吸聲性能門吸聲性能聲學(xué)包設(shè)計及驗證整車聲學(xué)包模型FEM/CADBOM/材料參數(shù)聲學(xué)包模型驗證現(xiàn)場TL測試Ideal load測試Real Load測試聲學(xué)包設(shè)計開發(fā)滿足

3、目標(biāo)性能聲學(xué)包開發(fā)聲學(xué)包調(diào)校及優(yōu)化密封性能檢測NPA分析聲學(xué)包優(yōu)化聲學(xué)性能成本/重量/尺寸材料類型/厚度聲學(xué)包對標(biāo)測試材料性能對標(biāo)吸聲材料性能隔聲材料性能子系統(tǒng)性能對標(biāo)面板子系統(tǒng)座椅等子系統(tǒng)整車性能對標(biāo)語音清楚度面板貢獻量第10頁聲學(xué)包開發(fā)流程指標(biāo)設(shè)定/分解標(biāo)桿研究NVHCAE/DVP驗證樣車調(diào)校聲學(xué)包對標(biāo)測試材料性能對標(biāo)吸聲材料性能隔聲材料性能子系統(tǒng)性能對標(biāo)面板子系統(tǒng)座椅等子系統(tǒng)整車性能對標(biāo)語音清楚度面板貢獻量第11頁吸聲系數(shù)測試法向入射吸聲系數(shù)無規(guī)入射吸聲系數(shù)傳遞損失測試駐波管法試驗室法阻尼材料測試Oberst 方法SAE 方法材料性能測試第12頁傳遞損失測試標(biāo)準混響室/全消聲室測試 混響

4、室/混響室測試現(xiàn)場傳遞損失測試傳遞損失仿真（VA One）子系統(tǒng)吸聲量測試標(biāo)準混響室ABS Cabin子系統(tǒng)性能測試第13頁聲學(xué)包開發(fā)流程指標(biāo)設(shè)定/分解標(biāo)桿研究NVHCAE/DVP驗證樣車調(diào)校聲學(xué)包指標(biāo)設(shè)定及分解地板/車門等TL地毯傳遞損失中控臺傳遞損失發(fā)動機艙/乘客艙吸聲系數(shù)艙蓋吸聲性能頂襯吸聲性能門吸聲性能第14頁/1/15聲學(xué)包指標(biāo)設(shè)定與分解第15頁聲學(xué)包開發(fā)流程指標(biāo)設(shè)定/分解標(biāo)桿研究NVHCAE/DVP驗證樣車調(diào)校聲學(xué)包設(shè)計及驗證整車聲學(xué)包模型FEM/CADBOM/材料參數(shù)聲學(xué)包模型驗證現(xiàn)場TL測試Ideal load測試Real Load測試聲學(xué)包設(shè)計開發(fā)滿足目標(biāo)性能聲學(xué)包開發(fā)第16

5、頁整車聲學(xué)包設(shè)計第17頁SEA 模版模型CAD/FE 輸入材料數(shù)據(jù)庫各向同性材料：密度，彈性模量，泊松比，阻尼損耗因子各向異性材料：密度，彈性模量，泊松比，阻尼損耗因子多孔吸聲材料：吸聲系數(shù)/表面阻抗，孔隙率，流阻、彎曲率，溫度特征長度，粘滯特征長度阻尼材料：密度，阻尼損耗因子，彈性模量，泊松比質(zhì)量材料：面密度 or IL or TL激勵譜庫不一樣工況下各面板聲激勵聲學(xué)包模型開發(fā)第18頁理想載荷及工作載荷作用下整車測試載荷譜及車內(nèi)聲場響應(yīng)測試子系統(tǒng)（如火墻、地板等）特征測試傳遞損失測試整車聲學(xué)包模型驗證第19頁整車狀態(tài)下NPA分析，明確關(guān)鍵傳遞路徑整車NPA診療第20頁聲學(xué)包設(shè)計與驗證第21頁

6、地板、火墻等板件傳遞損失優(yōu)化密封、填充等傳遞損失優(yōu)化部件子系統(tǒng)優(yōu)化第22頁發(fā)動機艙、頂襯、后備箱等吸聲性能設(shè)計部件子系統(tǒng)優(yōu)化Absorption, Sabine/m2 Frequency (Hz)Headliner Trim AbsorptionNHeadliner_WithFelt_v3NHeadliner_WithFelt_v2NHeadliner_WithFelt_Baseline第23頁聲學(xué)包開發(fā)流程指標(biāo)設(shè)定/分解標(biāo)桿研究NVHCAE/DVP驗證樣車調(diào)校聲學(xué)包調(diào)校及優(yōu)化密封性能檢測NPA分析聲學(xué)包優(yōu)化聲學(xué)性能成本/重量/尺寸材料類型/厚度第24頁密封性檢測鹽霧法超聲波法聲學(xué)包優(yōu)化NPA

7、 分析優(yōu)化目標(biāo)：聲學(xué)性能優(yōu)化約束：成本/重量/尺寸優(yōu)化變量：材料類型/厚度整車聲學(xué)包調(diào)校第25頁總結(jié)整車NVH開發(fā)流程中聲學(xué)包開發(fā)工作包含：對標(biāo)測試：吸聲、隔聲、阻尼，質(zhì)量、密度，空間分布、貢獻量，聲源級等等，關(guān)鍵制訂合理測試方案指標(biāo)分解：CAE分析：SEA模型、材料物性參數(shù)測試、聲源特征參數(shù)、NPA、制訂優(yōu)化方案實車調(diào)教：實車NVH測試、檢漏測試、部件子系統(tǒng)優(yōu)化等第26頁聲學(xué)包材料特征及測試方法Part 3第27頁聲學(xué)材料分類第28頁吸聲材料物理特性隔聲材料物理特性阻尼材料物理特性T&S 解決方案本節(jié)內(nèi)容第29頁吸聲材料物理特征第30頁多孔吸聲材料吸聲材料：含有大量內(nèi)外聯(lián)通微小孔隙和孔洞吸聲

8、機理黏滯性和內(nèi)摩擦效應(yīng)熱傳導(dǎo)效應(yīng)吸聲性能評價指標(biāo)法向入射吸聲系數(shù)混響室內(nèi)測試吸聲系數(shù)第31頁混響室法： ISO 354/GB T20247/ASTM C423聲學(xué) 混響室吸聲測量，測量結(jié)果為無規(guī)入射吸聲系數(shù)駐波管法：ISO 10532/ASTM E-1050/ASTM C384，測量結(jié)果為法相入射吸聲系數(shù)吸聲系數(shù)測試方法和標(biāo)準第32頁ISO 354 / ASTM C423 要求樣本太大，由SAE 聲學(xué)材料委員會主持研究標(biāo)準小樣本混響室測試相當(dāng)于ISO 354 / ASTM C423混響室體積1/10 （甚至更?。總€混響箱須利用標(biāo)準混響室進行標(biāo)定利用脈沖響應(yīng)法及施羅德原理 混響箱第33頁聲學(xué)

9、材料性能本構(gòu)方程Johnson-Champoux-Allard 開發(fā)5參數(shù)方程airflow resistivity , open porosity , tortuosity viscous characteristic length , thermal characteristic length 預(yù)測方法第34頁Flow resistivity：流阻，氣流流過結(jié)構(gòu)阻力，定義為其中 p 為氣流流過材料壓力損失Vairflow 為氣體流量，d為材料厚度測試標(biāo)準：EN 29053 std (ISO European std)幾何物理參數(shù)第35頁Open Porosity：開孔孔隙率，材料內(nèi)部流體體

10、積與材料總體積比值定義：閉孔孔隙率為零幾何物理參數(shù)第36頁開孔孔隙率測試（No Std）利用理想氣體恒溫壓縮（玻意耳定律）幾何物理參數(shù)測試第37頁Tortuosity：彎曲率，無量綱量，描述流體流過材料路徑彎曲程度定義： 其中，v 為流體流速，V 為均一體積測試方法（No Std）：電學(xué)方法幾何物理參數(shù)第38頁Viscous characteristic lengths：粘滯特征長度描述材料及內(nèi)部流體相互作用粘性力，定義：Thermal characteristic lengths：溫度特征長度描述材料及內(nèi)部流體之間溫度交換，定義：其中，v 為流體流速，V 為內(nèi)部流體體積， S 為內(nèi)部孔隙與材

11、料間接觸面積幾何物理參數(shù)第39頁Inverse method：遺傳算法，最小價值函數(shù)解幾何物理參數(shù)測試第40頁analytical inversion method幾何參數(shù)測試第41頁幾何物理參數(shù)測試第42頁材料拓撲分類Rigid Frame：結(jié)構(gòu)遠遠強于內(nèi)部氣體，如聚合物纖維、穿孔板等Limp：材料密度與內(nèi)部氣體密度相當(dāng)，結(jié)構(gòu)非自支撐，多是纖維類Elastic frame：結(jié)構(gòu)與內(nèi)部流體相互作用，如巖棉多孔吸聲材料分類聚合物纖維：Rigid Frame軟玻璃纖維：Limp巖棉： Elastic frame第43頁Poros-Elastic：需要知道力學(xué)參數(shù)楊氏模量（體積模量）泊松比內(nèi)損耗因子

12、力學(xué)性能參數(shù)第44頁準靜態(tài)測試方法(No Std)機械阻抗和側(cè)向變形力學(xué)性能測試第45頁準靜態(tài)方法有限元靜力學(xué)仿真：任意確定一個彈性模量和損耗因子，選擇不一樣泊松比計算，能夠取得 T 隨泊松比改變函數(shù)利用試驗測試取得 T 和仿真結(jié)果能夠得到材料泊松比力學(xué)性能測試第46頁準靜態(tài)方法有限元靜力學(xué)仿真：確定泊松比，改變不一樣彈性模量能夠取得壓縮剛度 K 隨楊氏模量改變函數(shù)利用試驗測試 K 和仿真結(jié)果能夠得到材料楊氏模量力學(xué)性能測試第47頁隔聲材料物理特征第48頁聲障：隔斷噪聲從一個空間向其臨近空間傳輸反射能力強，吸聲性能差材料密實，透射聲能小STL：傳遞損失隔聲材料（聲障）第49頁隔聲原理：質(zhì)量定律

13、 其中f為頻率，w為面密度雙墻結(jié)構(gòu)：同質(zhì)量雙層墻比單層墻隔聲量大5-10dB柔性材料：預(yù)防材料與結(jié)構(gòu)共振非開孔材料大質(zhì)量隔聲材料（聲障）第50頁經(jīng)典聲障材料Thermoplastic barriers with fillers(high mass per surface area)Barriers with fiber or foam decouplers Fiber/mastic/fiber constructions Lightweight impervious membranes 障板產(chǎn)品：地板系統(tǒng)、火墻絕緣板、密封材料隔聲材料（聲障）第51頁各種 STL 測試方法SAE J1400 空

14、氣聲隔聲性能試驗室測試方法ASTM E90 / ISO 140空氣聲隔聲性能標(biāo)準試驗室測試方法ISO 15186-1聲強測試法第52頁SAE J1400STL測試要求：混響室-半消聲室參考樣本（均勻柔性面板）隨機噪聲測量聲源及半消聲室內(nèi)SPL測試樣本隨機噪聲測量聲源及半消聲室內(nèi)SPL第53頁ISO140/ASTM E90STL測試要求：混響-混響測試Audio AmpllifierInternal light absorptionWalls with TL of 30 dB at 100 HzMicrophones systemSteel plate and sample position第5

15、4頁STL測試要求：混響-全消ISO 15186 聲強法第55頁阻尼材料物理特征第56頁通常為聚合物材料，用于面板表面降低 / 耗散振動耗散過程將機械能轉(zhuǎn)化為熱能常見阻尼產(chǎn)品：Asphalt Melt SheetsFoil Constrained Layer DampersSpray On ( Epoxy, Water based)Expandable Patch Constrained Layer (PCL)Laminated Steel Sheet阻尼材料第57頁阻尼材料應(yīng)用效果阻尼材料第58頁應(yīng)用FloorDash panelRoofDoorsBrakes阻尼材料第59頁SAE J671

16、利用基礎(chǔ)板自由振動衰減率測試復(fù)合材料振動阻尼SAE J1637 利用支撐鋼梁測試復(fù)合材料振動阻尼試驗室方法ASTM E756測試材料振動阻尼方法阻尼損耗因子測試標(biāo)準第60頁經(jīng)過振動衰減率測試阻尼方法能夠測試材料各種應(yīng)用對阻尼影響能夠取得特定頻率和隨溫度改變阻尼不能測試復(fù)模量信息測試要求基礎(chǔ)板件尺寸：500 x 500 x 6 mm共振頻率 145 to 165 Hz，常溫下自由振動衰減率不超出3dBSAE J671 測試方法第61頁/1/15SAE J671第62頁能夠在特定頻率和溫度下激勵阻尼桿確定共振頻率，并經(jīng)過半功率帶寬方法計算阻尼損耗因子對其它振動激勵和溫度下進行重復(fù)測量SAE J16

17、37 用于測試復(fù)合損耗因子，ASTM E756用于測試獨立材料Oberst Bar-SAE J1637/ASTM E-756第63頁T&S 處理方案第64頁CharacteristicsMaterial typePARAMETERSTANDARDMETHODOLOGYMass LayerFoamFiberAlpha SabineISO 354 and ASTM stdISO std Reverberant room ca 200 m3NoYesYesAlternative ABS-CAB methodNoYessee ABS-CAB cabineYessee ABS-CAB cabineTra

18、nsmission LossISO 140/x or ASTM equivalentISO 140/x std: 2 reverberant rooms face to faceYesYesYesEquivalent to ISO standard aboveAlternative: Reverberant room in the ground and Anechoic chamber on topYesYessee TL or ILYessee TL or ILNo standardAlternative: 2 box on top each other - Fiat-Peugeot met

19、hodYesYessee TL small Yessee TL small Insertion lossNo standardSame as TL above with unknown material layer laynig on top of fixed metal plateYesYessee TL or ILYessee TL or ILBulk ModulusNo standardMechanical stifness measurement and 3-d modelingNoYessee Bulk ModulusYessee Bulk ModulusDamping loss F

20、actorOberst method DIN/ISO stdYesYessee OberstYessee OberstSAE method stdYesYoungs modulusOberst method DIN/ISO stdYesYessee OberstYessee OberstPoisson RatioNo standardLaser beam static experimentYesYesAiflow ResistivityEN 29053 std (ISO European std)Forced air through sampleNoYessee Flow Resistance

21、Yessee Flow ResistancePorosityNo standardNoYesYesTurtuosityNo standardElectrical methodNoYessee TortuosityYessee TortuosityAbsorption + ImpedanceISO and ASTM standardsKundt Tube method Transfer FunctionNoYessee KundtYessee KundtNo standardKunt Impulse ResponseNoYessee KundtYessee KundtPlane wave Tra

22、nsmission LossNo standardsDouble Kundt tubeYesYessee KundtYessee KundtNo standardsDouble Kundt tube Impulse Response methodYesYessee KundtYessee KundtImpedance and physical modelNo standardNew Kundt tube versionYesYesSolutions 匯總第65頁Kundt tube：阻抗管系統(tǒng)SCS 9020B 系列駐波管吸聲系數(shù)復(fù)反射系數(shù)復(fù)表面阻抗傳遞損失復(fù)質(zhì)量密度復(fù)體積模量第66頁ISO

23、standard 10534-2 it is not very good actually and we do not recommend to follow it in total.Our recommendation it is to use the positions M1 and M2 or M2 and MII which are the original positions in the earlier ISO and are also the best one in our experience.Mic. Positions R and MI have been introduc

24、ed due to the latest revision of ISO 10534-2 which requires a higher Microphones distance for low frequencies. However, if you want to use position R, you shall move the sample about 15cm away to assure a minimum distance between the Mic. R and the sample. You just have to move backward the piston,

25、it is very simple.RM2M1MIIMIKundt tube：吸聲系數(shù)測試配置第67頁Microphones positions1 2Microphones positions3 4SampleSound Source1 or 2 Loads(anechoic terminations)unu*nTL 測試沒有相關(guān)ISO或者ASTM標(biāo)準3 microphones method or “single” load TL Modulus only4 microphones method or “two-loads” TL Modulus, f, ZcKundt tube：吸聲系數(shù)測試

26、配置第68頁From ISO 10534 it can be seen that Sound absorption coefficient of the material can be determined using Standardized Kundt apparatus with 2 methods:SWT “standing wave ratio” and TF “transfer function method”While the SWT intrinsically get to single Frequency values, steady state sinusoidal exc

27、itation, the TF is based on FFT and FRF so it get to expressed in a full spectrumA problem: how to derive 1/3 or 1/1 octave values from TF method?Common sense says: take the values at the Frequencies corresponding to 1/3 octave bands nominal value!New methodology based on the measurement of the reve

28、rberation time in the tube.It can be considered a kind of hybrid among ISO 10534 but it is more precise and energetically correct.The sound signal is an exponential sine sweep of which it is measured the Impulse Response Function IRF.By convoluting the IFR with 1/3 octaves IIR we obtain the from a “

29、whole” 1/3 octave bands and not just from a single Frequency line!Sine SweepIRFKundt device with add.on elements for T60Kundt Tube extended metodologies (T60)第69頁Everything is compatible with standard Kundt deviceCircled items are add-on for T60Squared items are standardSample IISample ILoudspeakerO

30、nly 1 micorphone is necessaryImpulse Response (from T60 measurment)A new method for the measurement of single and coupled absorption coefficients It is based on the reverberation time in the Kundt tubeThe method produces 1/3 octave band sound absorption values and complies with ISO-ASTM results but

31、resolves ambiguities in the conversion of FFT values into 1/3 octave values. The sound energy is injected at side and moves in both directions and build up the standing wavesAfter each impact of the plane waves with the samples at the ends the intensity of the waves is reduced yelding to the concept

32、 of Reverberation TimeReverberation time (T60) is obtained from the measurement of the impulse response using a methodology known as “exponential sine sweep”: Squared Impulse Response and Schroeder back-integration to evaluate the reverberation time in the tube with an exceptional S/N ratio. Compari

33、son of results for 0 using ISO-ASTM method (TF) and the Impulse Response (TF) for T60 evaluationTransmission Loss measurements in a tube can also be performed.The excitation signal is a sine sweep and the impulse response of each microphone position is determined. The maxima peaks shift of the measu

34、rements gives the distance x1 to x4 and the amplitude coefficient of the Complex Pressure function are determined and used to estimated the coefficient of Transfer Function Matrix Kundt Tube extended metodologies (T60)第70頁ABS Cabine: 混響箱系統(tǒng)SCS 9031 ABS Cabine樣本尺寸 1m*1.2m頻率范圍： 500 8000Hz 1/1 Octave 31

35、5 8000 Hz 1/3 Octave空間5個測試點，內(nèi)部配置自動旋轉(zhuǎn)定位裝置；墻壁由多層復(fù)合結(jié)構(gòu)制成，隔聲量優(yōu)于20dB(100Hz)；專業(yè)后處理軟件：基于施羅德原理，Windows XP第71頁SCS9023流阻測試（EN 29053）電子速度控制器標(biāo)定杯可調(diào)樣品夾具可替換凸輪直徑100mm管體，包含活塞和齒輪傳動電機1/2“ 麥克風(fēng)及附件專業(yè)后處理軟件Flow Resistivity：流阻測試系統(tǒng)第72頁SCS 9028 開孔孔隙率測試適合用于開孔性材料測試，如 纖維、毛氈、泡沫等高精度驅(qū)動控制，微米級空腔壓力差為0.3-1 mm Hg之間測試精度優(yōu)于 1 %Porosity：開孔率測

36、試系統(tǒng)第73頁SCS 9025 彎曲率測試系統(tǒng)（No Std）圓柱形水箱、測量箱試樣夾具、電極、管路及連接件桌面型寬頻帶功率推進器，帶有高、低通濾波器專業(yè)測量分析軟件包Turtuosity：彎曲率測試系統(tǒng)第74頁PAM-RC RoKCellsoftware determine parameters related to visco-inertial and thermal dissipation inside a porous material following JCAL (Johnson Champoux Allard Lafarge) model. It allows for the d

37、etermination of 5 parameters: the static air flow resistivity, the high frequency limit of the dynamic tortuosity, the viscous and thermal characteristic lengths the static thermal permeability. It is “unique” for 2 reasons:the implemented method consists in an analytical inversion of all non-direct

38、ly measurable parameters: it does not rely on any curve fitting; method described by Panneton & Olny in their and publications. It allows the determination of the static thermal permeability:a parameter introduced by Lafarge et al. to improve the description of the thermal dissipation inside porous

39、media. PAM-RC Software第75頁PAM-RC RoKCellsoftwareRoKCell main panel:IN the example it shows Normal incidence absorption coefficient measured vs. estimated resultscharacterization windows for visco-inertial (tortuosity, viscous characteristic length) main parameter is complex mass density.Characteriza

40、tion windows for thermal parameters (thermal characteristic length, static thermal permeability) main parameter is Bulk modulusPAM-RC Software第76頁PAM-RC RoKCellsoftware - How it works? As simple as 1, 2 and 3Preliminary:Get Kundt tube data: Complex impedance, TL, complex mass density and Bulk modulu

41、sGet Open porosity or try a first guess (0.8 to 0.9)Step 1Adjust cursors in the characterization windows for visco-inertial (tortuosity, viscous characteristic length) main parameter is complex mass density in the low frequency range until obtaining a good correspondance between experimental data an

42、d theoretical ones Step 2Adjust cursors in the Characterization windows for thermal parameters (thermal characteristic length, static thermal permeability) main parameter is Bulk modulus - in the mid frequency range until obtaining a good correspondance between experimental data and theoretical ones

43、 Step 3Go to PAM-RC RoKCell main panel (Normal incidence absorption coefficient, TL, or Impedance) and adjust porosity to obtain the best correspondance between measured vs. estimated resultsValidationResults check: Run “Auto” mode to estimate the whole set of parameters and check if the previous an

44、alytical results are confirmed.Standard physical model is JCAL with 6 parametersAlternatively it also works based on Delany and Bazley model with Flow resistivity as single parameter All experimental data, estimated data and other information are stored in “txt” readable files.PAM-RC Software第77頁SCS

45、 9026 彈性測試測試系統(tǒng)動態(tài)楊氏模量，動剛度，阻尼損耗因子等鋼&鋁制機械結(jié)構(gòu)步進式正弦信號發(fā)生器及閉環(huán)控制器靜態(tài)楊氏模量及泊松比測試選項包含加載機構(gòu)壓縮材料，經(jīng)過兩組多束激光測量側(cè)向變形，分辨率到達10 micron真空測試環(huán)境選項真空環(huán)境艙及真空泵，環(huán)境可到達100 mBASeismic table 桌面Mechanical stifness：彈性參數(shù)測試系統(tǒng)第78頁隔聲測試處理方案非標(biāo)準產(chǎn)品可依據(jù)客戶要求提供符合各種標(biāo)準要求大、中、小型隔聲測試方案第79頁SCS 9022 SAE 阻尼測試方案測試基礎(chǔ)鋼板 600 x 600m 5mm 厚承載板及彈性支撐裝置等ICP型力錘， 0 to

46、445N, 11.2 mV/N加速度傳感器，ICP型，靈敏度7mV/g專業(yè)后處理軟件SAE J671 阻尼測試系統(tǒng)第80頁Oberst Bar 阻尼測試系統(tǒng)SCS 9021 Oberst 測試系統(tǒng)測試專用臺架、可調(diào)整夾具及機械臂電磁激振器及電源適配器等高溫、非接觸感應(yīng)式位移傳感器位移傳感器信號輸入調(diào)理，BNC輸出參考鋼桿300 x10 mm 1mm 厚專業(yè)后處理軟件第81頁聲學(xué)包開發(fā)CAE仿真Part 5第82頁/1/15材料預(yù)測模型第83頁任意截面形狀圓柱孔內(nèi)空氣有效密度和有效模量其中材料預(yù)測模型-介觀力學(xué)第84頁剛性框架材料內(nèi)聲傳輸從幾何框架出發(fā)模擬多孔材料等效密度和模量難度很大，所以多數(shù)

47、建模采取了 phenomenological 理論（homogenization theory），其中 Johnson and Champoux and Allard 工作得到了廣泛認可很顯著，有效密度和有效模量取決于材料 5 個幾何參數(shù)airflow resistivity , open porosity , tortuosity viscous characteristic length , thermal characteristic length 材料預(yù)測模型-均質(zhì)理論第85頁表面阻抗及傳輸常數(shù)Delany and Bazley 模型適合玻璃棉和較軟巖棉材料預(yù)測模型-半經(jīng)驗公式第86頁

48、針對多孔彈性材料，并假設(shè)材料為均質(zhì)和各向同性材料預(yù)測模型-Biot 原理第87頁Statistical Energy AnalysisTypical applicationsAssemblies doors, cockpits, etc.Systems and sub sub-systemsComplete vehicles interior & exteriorTypical frequency range 500 to 10k HzAdvantagesGeometric detail not criticalAccurate to higher frequenciesSolution ti

49、mes relatively short (min.)Moderate computing power needsDisadvantagesRequires structural structural-acoustic expertiseValidation testing can be complicated complicated第88頁Hybrid FEM/SEA Method Typical applicationsComplete vehicle modelsComponentsTypical frequency range 10 to 10k HzAdvantagesNearly

50、full frequency rangeDisadvantagesEmerging technology Not much experience yet with this technology第89頁90Vehicle Airborne exitation How can we predict diffraction of source around vehicle in order to define exterior SPL for SEA model? Airborne SEA modelsourceOption # 1 : Use test data time consuming,

51、non predictiveOption # 2 : Use semi-empirical methods not accurateOption # 3 : Use simulation objective of this study第90頁91 / SubsystemPressure distribution at specific frequencySpace/frequency averaged pressure response in 1/3rd octave bandCPU timeAccuracyFMM solution outputSEA model inputEvaluatio

52、n of resultsVehicle Airborne excitation第91頁第92頁第93頁第94頁95FEM+PEM怎樣在整車有限元模型中模擬裝飾效果（0-400Hz）？?方法 # 1 :- 在白車身結(jié)構(gòu)有限元基礎(chǔ)上采取等效質(zhì)量/彈簧模擬裝飾，并對有限元聲腔進行等效方法 # 2 :- 采取完全 BIOT方程 描述多孔彈性材料，模擬結(jié)構(gòu)、裝飾和流體完全耦合響應(yīng)模型能夠正確描述物理現(xiàn)象及響應(yīng)第95頁PEM 描述內(nèi)裝飾、耦合效果而且計算耦合響應(yīng)FEM+PEM第96頁PAM-P AlphaCellis a software based on the Tranfer Matrix Metho

53、d (TMM/FTMM) It predicts the sound absorption or sound transmission performances of material layers. These layers can describe porous media, solid materials or fluids (air).User can apply simple and advanced models:Delany Bazley(1 parameter),JAC Johnson Champoux Allard(5 parameters),JACL Johnson Cha

54、mpoux Allard Pride Lafarge (8 parameters),Olny Boutin double prosoity model, micro-perforated facings with circular, rectangular or slit-like perforations,Biot model (isotropic skeleton, 4 parameters) which can be applied to all previous acoustic models to include the elastic effects of the porous f

55、rame. AlphaCell features:an intuitive interface, a database of materials (from experiments or from PAM-RC estimation), a project management for simulations, a customizable PDF report generation of the simulations, a data export/import for comparisons.PAM-P software：多層聲學(xué)包設(shè)計優(yōu)化第97頁Layer nameModelParameters1Foam 4 AA09 Fig11.11Acoustic: JCAElastic: Elastic (