柴油轿车车内低频噪声特性研究
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摘要
随着汽车工业的飞速发展以及人们对节能和环保的要求,车辆朝着高速化、轻量化方向发展,使得汽车噪声、振动与舒适性(NVH)问题凸现出来,质量轻量化是增大汽车车身结构低频振动和车辆内部噪声,特别是低频低沉轰鸣噪声的原因。作为轿车的一个重要发展趋势,柴油轿车的NVH问题更加突出。本文以某国产柴油轿车为研究对象,并应用数值模拟与实验相结合的方法来研究该轿车的车内低频噪声特性,在数值模拟过程中充分考虑了车身结构与车内空气的相互作用,使模拟结果更加接近实际情况。
首先在对轿车白车身模型进行实验模态分析的基础上,建立了轿车车身结构有限元模型,对该轿车的乘坐室由建立了空腔声学三维有限元模型与该车的车身板件-乘坐室空腔三维声耦合模型,并分别对以上各模型进行模态分析,通过白车身有限元模型模态与实验模态结果对比分析,验证了模型的正确性。然后利用多体动力学软件ADAMS建立该轿车多体动力学模型,提取发动机和路面对车身的激励力,应用结构及声场动态分析技术,对该车车身结构-乘坐室空腔声固耦合系统的动态特性给于了细致研究,并在此基础上分析了耦合系统的乘坐室声学响应,并与实车路面测试结果进行了对比,结果显示：随发动机转速升高时测试车辆乘坐室内的噪声值也有所增大,低速时车内噪声峰值较多,但幅值变化较小,高速时车内噪声水平明显升高,噪声峰值主要集中在几个频率点处。通过车内噪声测量值与计算值的对比可以看出,在较低频段两者符合较好,在较高频段两者相差较大。对车身板件振动声学贡献分析获得如下结果：后围板、地板中部、衣帽架板为主要正贡献板件,是该车车内噪声的主要声学贡献来源；最后针对板件贡献分析中对车内噪声较大的衣帽架板、后围板和中地板,对其中振动较剧烈的部位通过优化加强筋来增加局部刚度,优化后的分析结果表明：衣帽架板、后围板和中地板的优化效果较好,加强肋布置合理,能够较好的降低板件的振动幅度,达到降低车内噪声的目的。
With the rapid development of the automobile industry as well as people's energy-saving and environmental protection requirements, high-speed moving vehicles, light direction, making vehicle noise, vibration and comfort (NVH) problems emerged, the quality of light is increased Motor vehicle body structure of the low-frequency vibration and noise within the vehicle, in particular the resonance of low-frequency noise. Diesel cars which NVH issues become more prominent is an important development trend of the car. This paper made a diesel car for the study and application of numerical simulation and experimental combination of methods to study the low-frequency noise inside the car's characteristics, In the process of numerical simulation takes full account of the interaction of the air inside the vehicle and body structure so that the results closer to reality.
In the first, on the basis of the experimental modal analysis of the body in white, a car body structure of the finite element model, the cavity of cabin acoustic sound field of the finite element model and the structure-acoustic coupled model of the car structure and the cavity of cabin were established. And modal analysis was performed respectively for the models that were established above all. The correctness of the model was verified by the results of the comparison of the modal analysis by finite element model of the body in white and experimental modal analysis. Then the use of multi-body dynamics software ADAMS to build multi-body dynamic model of the car, the driving forces which derived from the engine and road were extracted respectively and the dynamic analysis techniques of the structure and sound field were applied. A detailed study of the dynamic characteristics of the coupled acoustic-structure system of the car was performed. The acoustic response of the coupled system by the driving forces which derived from the engine and road was analyzed and the road test results as well as calculated values were compared. The results show that: the magnitude of the car's interior noise increased as engine speed increase. The noise peak inside the vehicle was more at low-speed, but smaller changes in the amplitude. The level of the noise inside the car increased obviously and the noise peak was concentrated mainly in a few frequency points. Through the contrast of the measured value and calculated value of the cabin noise can be seen that the tendency was good to correspond with them in lower frequency bands and the gap was large in the higher frequency bands. The results of the further studies for acoustic contribution analysis of the vibration of the body panels showed that clothes tree panel, squab panel and the middle part of the floor panel which were the main noise source inside the car of contributions to the acoustics were the main panel for contribution; finally to direct at clothes tree panel, squab panel and the middle part of the floor panel which had larger contributions cabin noise in the analysis of panel contribution. And local stiffness was increased through the optimization of rebar of the more violent parts of vibration. The results for optimization analysis showed that there were good effects for clothes tree panel, squab panel and the middle part of the floor panel and the arrange of the strengthening rib were reasonable, which can reduce the amplitude of vibration apparently. The goal to reduce car noise had been to achieve.
首先在对轿车白车身模型进行实验模态分析的基础上,建立了轿车车身结构有限元模型,对该轿车的乘坐室由建立了空腔声学三维有限元模型与该车的车身板件-乘坐室空腔三维声耦合模型,并分别对以上各模型进行模态分析,通过白车身有限元模型模态与实验模态结果对比分析,验证了模型的正确性。然后利用多体动力学软件ADAMS建立该轿车多体动力学模型,提取发动机和路面对车身的激励力,应用结构及声场动态分析技术,对该车车身结构-乘坐室空腔声固耦合系统的动态特性给于了细致研究,并在此基础上分析了耦合系统的乘坐室声学响应,并与实车路面测试结果进行了对比,结果显示：随发动机转速升高时测试车辆乘坐室内的噪声值也有所增大,低速时车内噪声峰值较多,但幅值变化较小,高速时车内噪声水平明显升高,噪声峰值主要集中在几个频率点处。通过车内噪声测量值与计算值的对比可以看出,在较低频段两者符合较好,在较高频段两者相差较大。对车身板件振动声学贡献分析获得如下结果：后围板、地板中部、衣帽架板为主要正贡献板件,是该车车内噪声的主要声学贡献来源；最后针对板件贡献分析中对车内噪声较大的衣帽架板、后围板和中地板,对其中振动较剧烈的部位通过优化加强筋来增加局部刚度,优化后的分析结果表明：衣帽架板、后围板和中地板的优化效果较好,加强肋布置合理,能够较好的降低板件的振动幅度,达到降低车内噪声的目的。
With the rapid development of the automobile industry as well as people's energy-saving and environmental protection requirements, high-speed moving vehicles, light direction, making vehicle noise, vibration and comfort (NVH) problems emerged, the quality of light is increased Motor vehicle body structure of the low-frequency vibration and noise within the vehicle, in particular the resonance of low-frequency noise. Diesel cars which NVH issues become more prominent is an important development trend of the car. This paper made a diesel car for the study and application of numerical simulation and experimental combination of methods to study the low-frequency noise inside the car's characteristics, In the process of numerical simulation takes full account of the interaction of the air inside the vehicle and body structure so that the results closer to reality.
In the first, on the basis of the experimental modal analysis of the body in white, a car body structure of the finite element model, the cavity of cabin acoustic sound field of the finite element model and the structure-acoustic coupled model of the car structure and the cavity of cabin were established. And modal analysis was performed respectively for the models that were established above all. The correctness of the model was verified by the results of the comparison of the modal analysis by finite element model of the body in white and experimental modal analysis. Then the use of multi-body dynamics software ADAMS to build multi-body dynamic model of the car, the driving forces which derived from the engine and road were extracted respectively and the dynamic analysis techniques of the structure and sound field were applied. A detailed study of the dynamic characteristics of the coupled acoustic-structure system of the car was performed. The acoustic response of the coupled system by the driving forces which derived from the engine and road was analyzed and the road test results as well as calculated values were compared. The results show that: the magnitude of the car's interior noise increased as engine speed increase. The noise peak inside the vehicle was more at low-speed, but smaller changes in the amplitude. The level of the noise inside the car increased obviously and the noise peak was concentrated mainly in a few frequency points. Through the contrast of the measured value and calculated value of the cabin noise can be seen that the tendency was good to correspond with them in lower frequency bands and the gap was large in the higher frequency bands. The results of the further studies for acoustic contribution analysis of the vibration of the body panels showed that clothes tree panel, squab panel and the middle part of the floor panel which were the main noise source inside the car of contributions to the acoustics were the main panel for contribution; finally to direct at clothes tree panel, squab panel and the middle part of the floor panel which had larger contributions cabin noise in the analysis of panel contribution. And local stiffness was increased through the optimization of rebar of the more violent parts of vibration. The results for optimization analysis showed that there were good effects for clothes tree panel, squab panel and the middle part of the floor panel and the arrange of the strengthening rib were reasonable, which can reduce the amplitude of vibration apparently. The goal to reduce car noise had been to achieve.
引文
[1]朱昌慧,浅析汽车产生噪声的原因及控制措施,黑龙江科技信息,2008年第11期[2] Ratli.,M, FEV公司改善柴油机NVH性能的新设计技术,国外内燃机,1998年第5期
[3]吴光强、盛云、方园,基于声学灵敏度的汽车噪声声—固耦合有限元分析,机械工程学报,Vo1.2008
[4]庞剑、谌刚、何华,汽车噪声与振动—理论与应用,北京：北京理工大学出版社,2006.6
[5]邵宗安、王晚枝、张维峰,汽车乘座室结构与声学耦合特性的研究,汽车工程,Vo1.16,N0.2,1994
[6]GB1495-1979《机动车噪声允许标准》
[7]GB14952002《汽车加速行驶车外噪声限值及测量方法》
[8]ECER51/02《汽车加速行驶车外噪声限值》
[9]王季卿,噪声对人体各器官和系统的影响及防护,噪声与振动控制,1991年第Z1期
[10]惠巍、刘更、吴立言,轿车声固耦合低频噪声的有限元分析,汽车工程,2006年第12期
[11]S. H. Kim, J. M. Lee, M. H. Sung, Structural-Acoustic Modal Coupling Analysis and Application to Noise Reduction in a Vehicle Passenger Compartment, Journal of Sound and Vibration,1999,225(5), P989-999
[12]M. J. Allen, Stochastic Analysis of Structural Acoustic systems, University of Michigan PH.D Thesis,2001
[13]D. A. Stanef, C. H. Hansen, R. C. Morgans, Active control analysis of mining vehicle cabin noise using finite element modeling, Journal of Sound and Vibration, Volume 277, Issues 1-2,6 October 2004, Pages 277-297
[14]Chul Ki Song, Active vibration control for structural-acoustic coupling system of a 3-D vehicle cabin model, Journal of Sound and Vibration, Volume 267, Issue 4,30 October 2003, Pages 851-865
[15]On the virtual acoustical source in mapped infinite element, Journal of Sound and Vibration, Volume 261, Issue 5,10 April 2005, Pages 945-951
[16]Chang-Gi Ahn, Structural-Acoustic Coupling Analysis of Two Cavities Connected by Boundary Structures and Small Holes, Journal of Vibration and Acoustics, Volume 127, Issue6, December 2005
[17]汪斌,汽车乘坐室结构-声场耦合分析与降噪设计,重庆大学硕士学位论文,2000
[18]白胜勇,轿车车内噪声动态分析及其优化设计研究,同济大学博士学位论文,2000
[19]吴九汇,车辆内腔声固耦合分析的覆盖域方法研究,西安交通大学博士学位,论文2001
[20]马天飞,轿车NVH特性的刚弹耦合声固耦合一体化研究,吉林大学博士学位论文,2003
[21]刘涛,顾彦,丁平等,板块贡献量分析在汽车振动噪声设计中的应用,2003年MSC.Software中国用户论文集
[22]崔岸,王龙山,兰凤崇,结构优化有限元分析在客车概念开发中的应用研究,机械强度,2004,26(6)：710-715
[23]靳晓雄,张立军,汽车噪声的预测与控制,上海：同济大学出版社,2004：105-112
[24]邵毅明,王文兴,客车技术与研究,2004,6(5)：1-4
[25]高云凯,姜欣,张荣荣,电动改装轿车车身结构优化设计分析, 汽车工程,2005,27(1)：115-117
[26]马天飞,林逸,轻型客车NVH特性的刚弹耦合、声固耦合仿真研究,汽车工程,2005,27(1)：72-76
[27]李增刚编著,SYSNOISE Rev5.6详解,北京：国防工业出版社,2005.8
[28]LMS INTERNATIONAL N.V., LMS SYSNOISE Rev5.6 User Manual, March 2003
[29]GB/T18697-2002《声学汽车车内噪声测量方法》
[30]MSC.ADAMS Release Guide,2005
[31]Mladen Chargin and Otto Gartmeier. A Finite Element Procedure for Calculating Fluid-Structure Interaction Using MSC.NASTRAN. NASA Technical Memorandum 102857, December 1990
[32]Alan R. Bamett, Omar M. Ibrabin, and Timothy L. Sullivan. Transient analysis mode participation for modal survey trarget mode selection using MSC/Nastran dmap. 1994 MSC world users'conference Lake Buena Vista, Florida
[33]S. H. KIM, J. M. LEE, M. H. SUNG. STRUCTURAL-ACOUSTIC MODAL COUPLING ANALYSIS AND APPLICATION TO NOISE REDUCTION IN A VEHICLE PASSENGER COMPARTMENT. Journal of Sound and [34]Teik C. Lim. Automotive panel noise contribution modeling based on finite element and measured structural-acoustic spectra. Applied Acoustics 60 (2000) 505-519
[35]Oliver Wolff and Roland Sottek. Panel Contribution Analysis-An Alternative Window Method. SAE Paper,2005-01-2274
[36]Christian Soize, Jean-Christophe Michelucci. Structural shape parametric optimization for an internal structural-acoustic problem. Aerosp. Sci. Technol.4 (2000) 263-275
[37]Eddie Wadbro, Martin Berggren.Topology optimization of an acoustic horn.Comput.Methods Appl.Mech.Engrg.196(2006):420-436
[38]H.Denli, J.Q.Sun.Structural-acoustic optimization of sandwich structures with cellular cores for minimum sound radiation.Journal of Sound and Vibration 301(2007):93-105
[39]张军,兆文忠,谢素明等,结构声场耦合系统声压响应优化设计研究.振动工程学报,2005,18(4)
[40]C.R.Fredo, Anders Hedlund.NVH Optimization of Truck Cab Floor Panel Embossing Pattern.2005 SAE International,2005-01-2342
[41]张锦江,杨智春,具有多阶频率与振型约束的结构动力学优化设计,强度与环境,2007,34(1)
[42]张胜兰,基于HyperWorks的结构优化设计技术,北京：机械工业出版社,2007
[3]吴光强、盛云、方园,基于声学灵敏度的汽车噪声声—固耦合有限元分析,机械工程学报,Vo1.2008
[4]庞剑、谌刚、何华,汽车噪声与振动—理论与应用,北京：北京理工大学出版社,2006.6
[5]邵宗安、王晚枝、张维峰,汽车乘座室结构与声学耦合特性的研究,汽车工程,Vo1.16,N0.2,1994
[6]GB1495-1979《机动车噪声允许标准》
[7]GB14952002《汽车加速行驶车外噪声限值及测量方法》
[8]ECER51/02《汽车加速行驶车外噪声限值》
[9]王季卿,噪声对人体各器官和系统的影响及防护,噪声与振动控制,1991年第Z1期
[10]惠巍、刘更、吴立言,轿车声固耦合低频噪声的有限元分析,汽车工程,2006年第12期
[11]S. H. Kim, J. M. Lee, M. H. Sung, Structural-Acoustic Modal Coupling Analysis and Application to Noise Reduction in a Vehicle Passenger Compartment, Journal of Sound and Vibration,1999,225(5), P989-999
[12]M. J. Allen, Stochastic Analysis of Structural Acoustic systems, University of Michigan PH.D Thesis,2001
[13]D. A. Stanef, C. H. Hansen, R. C. Morgans, Active control analysis of mining vehicle cabin noise using finite element modeling, Journal of Sound and Vibration, Volume 277, Issues 1-2,6 October 2004, Pages 277-297
[14]Chul Ki Song, Active vibration control for structural-acoustic coupling system of a 3-D vehicle cabin model, Journal of Sound and Vibration, Volume 267, Issue 4,30 October 2003, Pages 851-865
[15]On the virtual acoustical source in mapped infinite element, Journal of Sound and Vibration, Volume 261, Issue 5,10 April 2005, Pages 945-951
[16]Chang-Gi Ahn, Structural-Acoustic Coupling Analysis of Two Cavities Connected by Boundary Structures and Small Holes, Journal of Vibration and Acoustics, Volume 127, Issue6, December 2005
[17]汪斌,汽车乘坐室结构-声场耦合分析与降噪设计,重庆大学硕士学位论文,2000
[18]白胜勇,轿车车内噪声动态分析及其优化设计研究,同济大学博士学位论文,2000
[19]吴九汇,车辆内腔声固耦合分析的覆盖域方法研究,西安交通大学博士学位,论文2001
[20]马天飞,轿车NVH特性的刚弹耦合声固耦合一体化研究,吉林大学博士学位论文,2003
[21]刘涛,顾彦,丁平等,板块贡献量分析在汽车振动噪声设计中的应用,2003年MSC.Software中国用户论文集
[22]崔岸,王龙山,兰凤崇,结构优化有限元分析在客车概念开发中的应用研究,机械强度,2004,26(6)：710-715
[23]靳晓雄,张立军,汽车噪声的预测与控制,上海：同济大学出版社,2004：105-112
[24]邵毅明,王文兴,客车技术与研究,2004,6(5)：1-4
[25]高云凯,姜欣,张荣荣,电动改装轿车车身结构优化设计分析, 汽车工程,2005,27(1)：115-117
[26]马天飞,林逸,轻型客车NVH特性的刚弹耦合、声固耦合仿真研究,汽车工程,2005,27(1)：72-76
[27]李增刚编著,SYSNOISE Rev5.6详解,北京：国防工业出版社,2005.8
[28]LMS INTERNATIONAL N.V., LMS SYSNOISE Rev5.6 User Manual, March 2003
[29]GB/T18697-2002《声学汽车车内噪声测量方法》
[30]MSC.ADAMS Release Guide,2005
[31]Mladen Chargin and Otto Gartmeier. A Finite Element Procedure for Calculating Fluid-Structure Interaction Using MSC.NASTRAN. NASA Technical Memorandum 102857, December 1990
[32]Alan R. Bamett, Omar M. Ibrabin, and Timothy L. Sullivan. Transient analysis mode participation for modal survey trarget mode selection using MSC/Nastran dmap. 1994 MSC world users'conference Lake Buena Vista, Florida
[33]S. H. KIM, J. M. LEE, M. H. SUNG. STRUCTURAL-ACOUSTIC MODAL COUPLING ANALYSIS AND APPLICATION TO NOISE REDUCTION IN A VEHICLE PASSENGER COMPARTMENT. Journal of Sound and
[35]Oliver Wolff and Roland Sottek. Panel Contribution Analysis-An Alternative Window Method. SAE Paper,2005-01-2274
[36]Christian Soize, Jean-Christophe Michelucci. Structural shape parametric optimization for an internal structural-acoustic problem. Aerosp. Sci. Technol.4 (2000) 263-275
[37]Eddie Wadbro, Martin Berggren.Topology optimization of an acoustic horn.Comput.Methods Appl.Mech.Engrg.196(2006):420-436
[38]H.Denli, J.Q.Sun.Structural-acoustic optimization of sandwich structures with cellular cores for minimum sound radiation.Journal of Sound and Vibration 301(2007):93-105
[39]张军,兆文忠,谢素明等,结构声场耦合系统声压响应优化设计研究.振动工程学报,2005,18(4)
[40]C.R.Fredo, Anders Hedlund.NVH Optimization of Truck Cab Floor Panel Embossing Pattern.2005 SAE International,2005-01-2342
[41]张锦江,杨智春,具有多阶频率与振型约束的结构动力学优化设计,强度与环境,2007,34(1)
[42]张胜兰,基于HyperWorks的结构优化设计技术,北京：机械工业出版社,2007