Noise Control of a Diesel Locomotive For Indian Railways

In this paper primarily an experimental work on the noise source identification done on a stationary diesel locomotive of a high power dual cab locomotive of the Indian Railways, followed by its control is presented. The locomotive is powered by a 2 stroke, 16 cylinder diesel engine providing a power of 4500 HP. The cab interior and the locomotive exterior under different engine speeds of the locomotive are presented with electrical loading on the generator driven by the engine. The interior noise sources are ranked by sound intensity measurements. The noise and vibration in the cab interior are also measured with noise and vibration instrumented locomotive while travelling between two railway stations approximately 30 km each way. The variations in the interior noise and vibration as a locomotive linear speed and the engine rotational speed are also presented. After the noise source characterization, noise control measures in terms of sound absorbing materials, barrier and dampening materials are used and a fresh locomotive manufactured at the manufacturing facilities of Indian Railways. The details of the material and their location are discussed in this paper. Finally results of significant noise reduction brought about in the front and rear cabs of the locomotive are presented.