| Light Rail Vehicle is one kind of modern conveyances, having the trait of efficiency, convenience and punctuality. But now people have attached more importance to the noise and vibration of the LRV. In the 60s, foreign counties began to pay more attention to this problem. In the 70s, Japan and Europe worked a lot to reduce the noise and vibration of the LRV. In the 80s, German and British made much experimentation about it .In our county, the work goes on slowly. So we must take serious attitude and efficient methods to reduce the noise and vibration of the LRV.The characteristics of the noise are topical and temporary. But the noise will do great harm to our bodies, including bringing much fatigue and pressure to the staff and the passengers, even making our hearing and nerve in bad conditions. So it is necessary for us to make great and efficient efforts to reduce the noise and vibration of the LRV.To analyze the noise better, we made experimentation in the LRV in November 1, 2004, measuring 9 different points in the interior of the vehicle when it was in the different working conditions. The HEAD acoustics measurement and analysis system is used in recording signal and data. Through the experimentation, we can make conclusions that the noise situation is serious in the LRV, which consists of the wheel-rail noise including rolling noise, structure noise ,friction noise and strike noise ;the working noise of the equipments, e.g. traction electric machine, ventilator, compressor and effectors ;the noise of compressed air. The frequency of the noise in the LRV is between 630～1250Hz, 800Hz and 1000Hz are the top frequency. Until now, we have begun with our work in the field of absorbing the noise, insulating the noise, absorbing the vibration, insulating the vibration, including selecting good materials that absorb and insulate the noises better. Due to the particularity of this vehicle, I have designed one kind of muffler to reduce the noise made from the...
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