A Simulation and Experimental Analysis of In- Terior Noise in an Ambulance and Noise Re- Duction with Damping Materials
نویسندگان
چکیده
Based on the theory of multi-body system dynamics and the method of finite element and boundary element, the finite element model of vehicle body and 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 20-300Hz. 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 point’s SPL peak and the optimal treatment was finally confirmed. Finally, the structural modification with damping materials is performed to the most contributing panels and the experimental results indicate that maximum SPL peak is decreased by 11dB and OSPL is decreased by 3dB.
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