Search Results

The use of iterative solver has been explored in the stress analysis of the center plate of a clutch and brake combination, where normally direct solvers are used. Many times after making the finite element model the analyst realizes that he has a very large model and his system is unable to solve it. Re-meshing the model is the only other choice. Analysts hesitate to use the alternative approach of iterative solvers since they are fairly new. Hence it was decided to compare results using direct and iterative solvers. It is concluded that iterative solvers can be used successfully for very large problems.

The aim of this analysis is to study the effects of flexibility of the suspension components like upper control arm, lower control arm and knuckle on the suspension forces as experienced by a vehicle. An independent front suspension, which was being proposed for a vehicle, has been used for this analysis. A rigid body quasi-static analysis was first performed. Later a finite-element model of the suspension first with rigid elements and later with flexible elements was analyzed using non-linear large deflection and compared with the rigid body results. It is found that flexibility of the suspension components only have a local effect and not much of a global effect.

A case study of failure analysis of a cast iron center plate of a clutch and brake combination, used in presses to stamp automotive components, using finite element analysis has been presented. To predict mechanical failures, it is quite common to use maximum principle stresses for brittle materials like cast iron. However, in this analysis, the stress plots could not account for the cracks in the failed samples. A metallurgical test showed that the samples had been subjected to high thermal loads on the clutch face. A thermal analysis, after assuming that the center plate was behaving as a mild ductile material, correlated analysis with actual failure.

A case study of the application of shape optimization technique to the design of the third cross-member of an automotive chassis has been presented. Its fundamental frequency is only marginally higher than the maximum operating frequency of the transmission and drive shaft, which are mounted on this cross-member. The objective is to raise the cross-member frequency as high as possible so that there is no resonance and resulting fatigue damage. A sizing optimization indicated that the mass was a predominant factor. Shape optimization using approximate direct linearization method was performed and a number of design directions were obtained. The fundamental frequency of the cross-member was raised by about 4 Hz.