Noise Research Of Truck's Cab

With the flourish development of industry ,agriculture,city traffic transport and tour enterprise in China, the possession of automobile of china have sharply increased in recent years. As a result , more and more problems about vehicle noise and vibration has arisen. The control of vibration and noise is vital to environmental protection,the auto's flatness and endurance. At the same time, the manufacturers of auto are contriving to curtail the period between model design and manufacture.Statistical Energy Analysis is a module measure, which use relationship of energy flow to evaluate dynamics, vibrating response level and sound radiation of the mulriple and syntonic assembly structure. SEA adapt to high frequency zone, especially in high module density. Traditional numerical value account, such as finite element method and boundary method, have acquired success in stress and vibration module, but it has obviously limits on noise application. It is proved to be successful by practice that SEA is a good method for noise emulation analyse.This paper illuminate how to build analyse the module of noise-vibration emulation and trial mixture. Establishing a suit of 3D modeling and trail criterion method, and prosecuting deeply theory study for SEA parameters.Expounding the basic theory of subsystem partition ,setting up the 3D module of the truck's cab ,putting forward the principle of subsystem partition in the process of factual modeling.Aiming at different structure, it founds a series of formulae of SEA parameters, such as module density, damping loss factor(DLF) and couple loss factor(CLF). Especially, because AutoSEA doesn't provide the value of DLF which must come from trail, it gives a detailed experimental criterion and measures the parameters needed in the study.Setting up formulae of converting the energy into all kinds of dynamics response, it apply various SEA parameters to the 3D module, then calculate the module and get the value of noise level of the subsystem which is near the driver's ear., simply analyzing the value finally.Educing the dominating energy flow by the analyzing of result, based on which it brings forward some pertinence measures to reduce the level of noise and vibration, and it can distinctly depress the noise level of the cab. The study of this paper can offer some guidance and reference on how to use SEA and AutoSEA to carry through noise-vibration study,set up the mixture analyze module of emulation and experiment,how to effectively reduce the noise level of truck cab.