Vehicle Body Panel Acoustic Contribution Analysis and Optimization

The noise of a cab directly affects the comfort and labor efficiency of the operators. The optimization of the structure-borne transmission path can obviously reduce the cab noise. The method of panel acoustic contribution analysis (PACA) is used to reduce structure noise. However, most studies only consider the panel acoustic contribution of a single frequency, without considering the contribution of major frequencies synthesis to confirm the optimized panels. In this paper, a novel method is proposed based on composite panel acoustic and modal contribution analysis and noise transfer path optimization in a vibro-acoustic model. First, the finite element model (FEM) and the acoustic model are established. Based on the acoustic transfer vector (ATV) method, a composite panel acoustic contribution analysis method is proposed to identify the panels affecting the noise of the field point. Combined with the modal acoustic contribution of the modal acoustic transfer vector (MATV) method, the noise field point is confirmed in the area which has the most significant influence. Second, the optimization algorithm NLOPT which is a nonlinear optimization is applied to design the areas. The noise transfer path optimization with vibroacoustic coupling response can quickly determine the optimal thickness of the panels and reduce low-frequency noise. The effectiveness of the proposed method is applied and verified in an excavator cab. The sound pressure level (SPL) the driver’s right ear (DRE) decreased obviously. The acoustic analysis of the composite panel acoustic contribution and modal acoustic contribution can more accurately recognize an optimized area than the traditional PACA. This method can be applied in the optimization of the structure-borne transmission path for construction machinery cab and vehicle body.

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Topology Optimization of Gearbox to Reduce Radiated Noise

Volume 10: ASME 2015 Power Transmission and Gearing Conference; 23rd Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2015-48086 ◽

2015 ◽

Author(s):

J. P. Wang ◽

G. Liu ◽

S. Chang ◽

L. Y. Wu

Keyword(s):

Topology Optimization ◽

Sound Pressure Level ◽

Sound Pressure ◽

Pressure Level ◽

Dynamic Loads ◽

Field Point ◽

Radiated Noise ◽

Contribution Analysis ◽

Acoustic Contribution ◽

Mode Order

In this paper, topology optimization of gearbox to reduce the radiated noise is studied based on the analysis of modal acoustic contribution and panel acoustic contribution. Firstly, the bearing dynamic loads are obtained by solving the dynamic equations of gear system. Secondly, the vibration of gearbox is calculated using FEM and the radiated noise is simulated using BEM by taking these bearing dynamic loads as excitations. Thirdly, the panel having larger contribution to the sound pressure level (SPL) at a specific field point is found by panel acoustic contribution analysis (PACA), and this panel is taken as design domain. The mode order with larger contribution is determined by modal acoustic contribution analysis (MACA), and making corresponding natural frequency becomes far away from excited frequency is taken as a constraint. Finally, the topology optimization of gearbox is completed using SIMP method, and the ribs are arranged according to the optimization results. The results show that the equivalent sound pressure level at objective field point can be reduced obviously by using this method.

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Minimizing vehicle noise and weight using panel acoustic contribution analysis

Optical Engineering ◽

10.1117/1.601660 ◽

1998 ◽

Vol 37 (5) ◽

pp. 1456 ◽

Cited By ~ 5

Author(s):

Gordon M. Brown

Keyword(s):

Vehicle Noise ◽

Contribution Analysis ◽

Acoustic Contribution

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Structural-Acoustic Analysis of Automobile Passenger Compartment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.236-237.175 ◽

2012 ◽

Vol 236-237 ◽

pp. 175-179 ◽

Cited By ~ 1

Author(s):

Shu Wen Zhou ◽

Si Qi Zhang

Keyword(s):

Frequency Response ◽

Acoustic Analysis ◽

Ride Comfort ◽

Vehicle Body ◽

Response Analysis ◽

Passenger Compartment ◽

Vector Method ◽

Acoustic Cavity ◽

Road Roughness ◽

Acoustic Contribution

Besides the performances of handling, stability, ride comfort, power and fuel economy, the sound pressure levels in the automobile passenger compartments heavily influence the customer’s purchasing decision. The interior acoustics of automobile passenger compartment was analyzed in this paper. The frequency response analysis was performed on the vehicle body due to road roughness. The frequency response of vehicle body’s output spectrum, nodes’ velocity is used as the boundary condition of the acoustic cavity. With boundary element method and acoustic transfer vector method, the panel acoustic contribution was analyzed. By modifying the stiffness, damping or mass of the corresponding panel, the acoustic pressure levels at the driver’s and passenger’s ear were decreased.

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Interior sound field refinement of a passenger car using modified panel acoustic contribution analysis

International Journal of Automotive Technology ◽

10.1007/s12239-009-0010-8 ◽

2009 ◽

Vol 10 (1) ◽

pp. 79-85 ◽

Cited By ~ 10

Author(s):

X. Han ◽

Y. -J. Guo ◽

H. -D. Yu ◽

P. Zhu

Keyword(s):

Sound Field ◽

Passenger Car ◽

Contribution Analysis ◽

Acoustic Contribution

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Panel Contribution Analysis Based on FEM, BEM and Numerical Green’s Function Approaches

Journal of Theoretical and Computational Acoustics ◽

10.1142/s2591728518500378 ◽

2018 ◽

Vol 26 (03) ◽

pp. 1850037

Author(s):

Kirill Shaposhnikov ◽

Mads J. Herring Jensen

Keyword(s):

Green’S Function ◽

Green's Function ◽

Noise Level ◽

Acoustic Pressure ◽

Boundary Element Methods ◽

Numerical Techniques ◽

Structural Vibrations ◽

Contribution Analysis ◽

Pros And Cons ◽

Acoustic Contribution

The panel acoustic contribution analysis is used to determine the contribution of vibrating panels to the noise level inside closed spaces like a car cabin. The use of numerical techniques makes it possible to rate the panels according to their contributions accounting for the interaction between the structural vibrations and the acoustic pressure at a listening point. We consider the application of the finite and boundary element methods and the numerical Green’s function approaches to the problem and discuss the pros and cons regarding their use. The results show that the numerical Green’s function approach coupled to structure can be effectively used for the panel contribution analysis in situations with multiple panels and few listening points.

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Simulation Analysis of an Ambulance Carriage Interior Noise

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.535.581 ◽

2014 ◽

Vol 535 ◽

pp. 581-585

Author(s):

Shi Ke Hou ◽

Song Bai ◽

Hao Jun Fan ◽

Hui Ding ◽

Yong Zhong Zhang ◽

...

Keyword(s):

Finite Element ◽

Boundary Element ◽

Simulation Analysis ◽

Coupled Model ◽

Element Model ◽

Simulation Software ◽

Vehicle Body ◽

Field Point ◽

Acoustic Contribution ◽

Multi Body

Based on the theory of multi-body system dynamics, the analytical method of finite element and boundary element, the finite element model of vehicle body, the rigid-flexible coupled model of vehicle and the acoustic boundary element model of carriage were established by applying a variety of simulation software. Road roughness was simulated and the SPL of field point in carriage under the excitation was computed at the frequency range of 20-150Hz. Considering the size and the positive /negative nature of panels acoustic contribution at SPL peak of field point, damping treatments were taken on different combinations of panels to decrease multiple field points SPL peak and the optimal treatment was finally confirmed. The results showed that noise reduction measures can generally decrease the SPL peak around the crew.

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