Modal Analysis of Heavy Vehicle Truck Transmission Gearbox Housing Made from Different Materials

Heavy vehicle truck transmission gearbox housing is subjected to load fluctuations, harmonic excitation, gear meshing excitation, gear defects, varying speed and torque conditions. Transmission errors and internal excitations are the root cause of vibration and noise. The main objective of this research work is weight calculation and modal analysis of gearbox housing. For weight calculation four different materials have been selected, apart from weight calculation the material mechanical properties influence on natural frequency and mode shape of transmission gearbox housing was also simulated using modal analysis. Grey cast iron FG260, Grey cast iron HT200, structural steel and Al alloys are the four materials used for the weight calculation process. Zero displacement constraint based boundary condition was applied for simulation. FEA based numerical simulation method was used to find the natural frequency, mode shapes and weight calculation of housing. The FEA simulation results show that the natural frequency of all materials varies (16694655) Hz. In weight calculation the weight of Al alloys housing is minimum (21.102 kg).The housing weight of Grey cast iron HT200 and FG260 is same, 54.85 kg. The density of structural steel is high, which increases the weight of housing as 59.80 kg. The modal analysis results show the lateral vibration, axial bending vibration, torsional vibration, and axial bending with torsional vibration. The vibration signature patterns for first twenty modes were studied for four different materials. Solid Edge and Pro-E software have good feature suited for complex geometric modeling. FEA based software Ansys 14.5 is used for modal analysis. The result of this research work has been verified with experimental result available in literature.