Vibro-Acoustic Analysis of a Simple Gear Box

Mesh forces of helical gears produce forces and moments in bearings, which generate the housing vibration, and noise radiates. It is difficult to know the noise contribution of a gear box, because the gear box usually has very complex geometry. This work used a cylindrical shell-type gear box with end circular plates to understand the noise and vibration characteristics of a simple gear box and investigated the noise and the vibration of the helical gear box due to the force excitation. The helical gear box of this study consisted of a pairs of helical gears, shafts, bearings, and a gear box. Finite element analysis for the helical gear box calculated mode shapes and natural frequencies and the forced harmonic response by the commercial software. The models were validated by the impact test. Using the forced harmonic response, acoustic analysis was conducted by the commercial software and relations on vibration and noise were discussed.