CAB Noise Control And Research Of Engineering Machinary

Noise is an important topic of engineering machinery now. With the development of environment protection and human health awareness, noise is paid more attention on. Noise certificate must be gotten when your product enters Europe market. Our regulation shorten difference with Europe regulation gradually and give two stage of noise plan. Noise is a new technical for engineering Machine Company. It is also key success factor of engineering company. For products compliance and noise basis creation, this thesis research on wheel loader machine noise reduction with the knowledge learnt by myself.Noise reduction model is set by this thesis with study of acoustic knowledge and wheel loader structure firstly. Main potential noise resource and three noise propagation paths are assumed. These all provide direction of the following noise reduction.Structure born noise is removed from main contributor by FEA analysis and vibration analysis firstly. Then, engine noise and hydraulic noise are defined as main contributor by frequency spectrum analysis and 1/3 octavo analysis of basic wheel loader noise test result. Noise reduction solutions of engine exhaust noise, fan noise and hydraulic noise are designed as their acoustic mechanism. Engine hood is optimized with SONIC+software on noise reduction. At last, this thesis successfully accomplishes design target with 4 dB noise reduction after all solutions applied on wheel loader. These solutions also can be used by stage II noise project.From successful wheel loader noise reduction, noise reduction model’s effectiveness is proven. Engine (exhaust, fan) noise and hydraulic noise is proven as main resource. Air propagation path is proven as main path.