Noise Analysis And Control During Heavy Dump Truck Accelerating Period

Noise has become a remarkable pollution.70%of urban noise originates from the traffic noise,and traffic noise is currently one of the most important urban pollution,it is also a important evaluate indicator of the vehicle environmental performance. Traffic noise affects people’s daily lives and rest, even harms people’s health, Effect on human hear system,example as cause the human hearing to drop, hearing loss, disturbs human’s sleep and rest, influence language exchange. Affects people’s sense of hearing system, besides affect human’s cardiovascular system, digestive system, nervous system and other internal organs.In cardiovascular caused by high blood pressure, disruption of the heart etc..In digestive Caused by gastric ulcer. In the nervous system, Noise can cause insomnia, fatigue, dizziness, headache, memory loss and other symptoms,therefore, Control the noise level is imminent. In recent years, Noise research and the noise reduction methods are constantly improving, But are still not fully resolved. Particularly heavy trucks generally use diesel engines, its noise reduction work required in-depth study.TG is the heavy dump truck which produced by the some motor company.In using,its external noise surpassed the ECE R51noise standards, The models affected exports to Europe.Aiming at this situation,this company organized the related companies to measure the noise of heavy dump truck on the spot.There was disparity between the measuring results and the Europe standard.Therefore,this company and the related supporting factories organize the technical personner to research immediately to reduce the noise and meet the demands of national noise emission Europe standard.The acoustics elementary knowledge,the noise production reason as well as the measures of noise control were introduced,and then the basic parameters and the equipment of TG truck,the noise test situation and so on were described.Finally,using Noise meter,Sound-level meter, noise sources outside of truck to be identified and separated, it concluded that the vehicle engine noise and transmission noise were the main noise source. According to the actual situation designed corresponding acoustic cover, Sound insulation board and damping plate structure, a variety of sound absorption and sound insulation materials were tested and analyzed, According the main noise source characteristics of tested heavy dump truck, reasonable choice of sound absorption,sound insulation materials and noise control program, noise reduction was carried out.Through compared the noise reduction before and after the car exterior noise,after took noise reduction measures, the dynamic acceleration noise of tested car from82.92dB (A) down to79dB (A), able to meet the European ECE R51standard on vehicle noise limits.