Prediction and simulation of internal train noise resulted by different speed and air conditioning unit

Railway noise is a problem not only for the train passenger inside but also from public and environment outside the train. The noise of railway is contribution from the noise of wheel, track and the friction of both. Other components such as electrical instruments, mechanical equipment and structure construction add the noise level of the train. This noise can be predicted as the function of the train velocity. By knowing, the noise level at certain speed, the noise at another speed can estimated accurately. In this research we obtained an error value of estimated noise level about 2.6 dB and 0.375 dB in the center of train car.