Himanshu Jaiswal

Material-Based Vibration Characteristic Analysis of Heavy Vehicle Transmission Gearbox Casing Using Finite Element Analysis

Transmission system is the most important part of the vehicle assembly. Truck transmission casing was subjected to vibration induced by the vehicle running, varying speed, and torque conditions. It is required to find the natural frequency and mode shape for accurate prediction of transmission casing life and prevent it from damage. The main objective of this research work is to find the influence of transmission casing material on natural frequency and mode shape of free vibration. Casing is made of material like cast iron, Al alloys, Mg alloys, structural steel, and composites. In this paper, the free vibration analysis of transmission casing has been performed by finite element simulation using ANSYS 14.5 software. The vibration patterns for first twenty modes were studied for all types of materials. The mode shapes show that the natural frequency of all materials varies in the range of 1,000–3,800 Hz. The analysis results were compared with experimental result available in the literature.

FEA Based Study of Loose Transmission Gearbox Housing

Transmission gearbox housing is subjected to noise and vibration induced by internal harmonic excitation. The internal harmonic excitation produces a dynamic mesh force, which is transmitted to the housing through the shafts and bearings and causes transmission failure. The main objective of this research work is to study the relation between the transmission vibration and the positional fixed constraints of vehicle frame by comparing the free vibration results of zero displacement constraint condition to positional constraint of the different number of connecting bolts. The vehicle gearbox housing is mounted on vehicle frame using connecting bolts fixture. The present design of heavy vehicle truck transmission housing is mounted on vehicle frame using 37 connecting bolts on five different positions. The study has been completed in two parts, in first parts all 37 connecting bolts were fixed on vehicle frame and in second part of study the front and bottom positional bolts were loosened to study the relation between vibration and constraint connecting bolts. Reciprocity Principle was used to apply the loads on housing. The first 20 vibration mode shape and natural frequencies were calculated using ANSYS 14.5. The study has theoretical and practical importance for the structure optimization of gearbox housing. ANSYS 14.5 is used as FEA based analysis tool. The natural frequency for zero displacement condition varies from 1669 Hz to 3576 Hz and for loose transmission housing frequency varies from 750 Hz to 3802 Hz. The analysis results is verify with experimental results available in literature.

Modal Analysis of Hand-Arm Vibration (Humerus Bone) for Biodynamic Response Using Varying Boundary Conditions Based on FEA

The main objective of hand-arm vibration (HAV) study is to identify the effect of vibration on human hand. Humerus bone is a long bone in the arm or forelimb that connects the shoulder to elbow. Free vibration analysis was performed to know the natural frequencies and natural vibration modes and identify the fracture location of the bone through the computer simulation based on FEA. Finite element analysis is an approximation technique used for the analysis of complex objects and geometries. The humerus bone analysis is subjected to free–free and fixed–fixed boundary conditions. For these two different boundary conditions, natural frequencies and natural vibration modes were identified. The mode shape shows that the natural frequency of free–free boundary condition varies from 0 to 1,185.3 Hz and for fixed–fixed boundary condition 943.36 to 7,703.9 Hz. On the basis of these two boundary conditions, mode shape is determined and fracture location can be easily notified. To prevent the fracture of humerus bone, external excitation frequency must be avoided to coincide with these natural frequencies. The results were compared with experimental results available in literature. For the design of humerus bone model, SOLID EDGE software is used and the model is imported in ANSYS R 14.5 (FEA based software) for the free vibration analysis.