外文翻譯----降低汽車噪聲的方法-汽車設(shè)計(jì)(完整版)
【正文】 e the exciting force and the engine parts of the exciting force response, which means transformation of acoustic source local oscillator. However, it is difficult to control noise sources when necessary in the route of transmission of noise to take measures, such as sound absorption, sound insulation, noise reduction, vibration and vibration isolation measures. Motor vehicles and vehicle vibration and noise reduction level of power, economy, reliability and strength, stiffness, quality, manufacturing costs and use are closely related. engine to reduce vibration and noise of the engine noise is the focus of automotive noise control. Engine vibration and noise are generated at source. Engine noise is from fuel bustion, valve bodies, gears and piston timing noise percussion synthesis. (1) ontology engine noise Lower engine noise will be ontological transformation of local oscillator sound sources, including methods such as finite element method analysis and design engines, selection of soft bustion process, improve the structure of the body stiffness, with the use of tight space, reduce noise cylinder cover. In addition, give the engine Tu damping material is an effective approach. Damping materials can kiic energy into thermal energy. To deal with the principle of damping is a damping materials and ponents into its vibrational energy to consume. It has the following structure: Freedom damping layer structure, and spacing of freely damping layer structure, and constrained damping layer structure and spacing of constrained damping layer. It is clear that the adoption of a decrease of resonance amplitude and accelerated the decay of free vibration, reducing the various parts of the ChuanZhen capacity, an increase of parts at or above the critical frequency of vibration isolation capacity. At present, some countries have designed an engine experts active vibration isolation system to reduce engine vibration, in order to achieve the purpose of noise reduction. (2) intake noise Engine intake noise is one of the main noise source, the Department of the engine noise of air power, with the engine speed increases to strengthen. Nonsupercharged engine intake noise major ponents, including the cyclical pressure fluctuation noise, vortex noise, the cylinder of the Helmholtz resonance noise. Diesel engine supercharger intake noise mainly from the turbocharger
畢業(yè)設(shè)計(jì)相關(guān)推薦
鄂ICP備17016276號(hào)-1