Since most of main noise sources of the railroad vehicle are transmitted to the passenger's ear through the vibration of the panel, the sound insulation performance of the panels should be high enough to protect the passenger's ear from the noisy environment. Specifically, the composite materials which are generally used for reducing the weight of the vehicle compartment have the low insulation performance, thus noise control actions should be taken appropriately by considering the insulation performance of the panels. In this study, the insulation performances of the inner/outer panels of the compartment are evaluated. In addition, the contribution of the insulation performance of aluminum door is estimated and compared to those of composite panels. The results can furnish an in-depth understanding of the insulation characteristics of the panel of railroad vehicle.
