Study on characteristics of noise of diesel locomotive

Noise test has been done for a certain type of diesel locomotive under different working conditions for outfield and cab, and analyzed the noise characteristic of each test point. Through the analysis of the data :The sound pressure level of point D, E, I, J of 12 test points of outfield test is bigger due to the effect of noise source; The changing of working condition of locomotive mainly makes test points of the outfield produce big change in the high frequency after 400 Hz; The opening of cooling fan makes sound pressure level of test points of outfield improved obviously; The noise of cab is mainly produced by combined action of vibration of locomotive wall and external noise source: External noise source influences the whole frequency band of the cab, vibration makes individual frequency have big increased