Free Vibration and Material Mechanical Properties Influence Based Frequency and Mode Shape Analysis of Transmission Gearbox Casing

Abstract

The main objective of this research work is to study the effect of mechanical properties of materials on natural frequency and mode shapes of heavy vehicle gearbox transmission casing. Material mechanical properties play an important role for evaluation of frequency, deformation, stress and strain. Four materials have different density and the origin of material is also different. Grey cast iron has damping property, structural steel has high density and rigidity, Al and Mg alloys have low density. Free vibration study was performed for the vibration response study of casing. Grey cast iron grade FG 260, Structural Steel, Al alloy and Mg Alloy materials were analyzed on the design and vibration index. The free vibration study of casing was performed using finite element simulation. The vibration response for all materials shows the variation of natural frequency (1002-3879) Hz and various vibrations mode shapes. The vibration responses for first twenty modes were studied. Solid Edge and Pro-E was used for CAD designing of transmission gearbox casing. FEA based ANSYS 14.5 is used for modal analysis. Fixed- fixed constraint based boundary condition was used by constraining the connecting bolts hole. The transmission casing is tightly mounted on vehicle frame using connecting bolts. Loose transmission casing causes heavy noise and vibration problem. The simulation results were compared with experiment results available in literature.