Experimental Study on Vibration and Noise of the Railroad Gear Unit using ODS and Beamforming Method

Abstract

The vibrations and noises occur from a drive system likely to increase when the driving speed of the Shinkansen improves. Particularly, the noise generated from gear case become high correlation in 1st meshing vibration occor from the pinion and gear. we measured vibrations and sounds of gear systems under running conditions in order to analysis the property of the systems. however, the separation of the sound source may be difficult because the rolling noise is included at the frequency that is almost the main frequency of gear noise(approximately,1kHz) .In this paper, We carried out bench test with fundamental modal analysis, Operating Deflection Shape analysis(ODS) and Beamforming analysis to acquire more detailed measured data on a noise generated from the gear systems. we found that the center of vibration and the sound radiation exist around bearing device or plate part of the bearing neighborhood.