MODEL DESCRIPTION
The solid finite element model of the knuckle has been built using a second order solid tetrahedron element. The model has 27,832elementand 47,291 nodes. The loads are applied at the upper, lower and tierod ball joints. The loads are applied using dummy springs and displacements. We have three dummy springs (representing each of the three directions) at each of the knuckle vertical load points. One end of the springs is attached to the knuckle while the other end is free to move only in one direction. A specified displacement is given at that end to generate a suitable load. A preliminary NASTRAN stress analysis of the FE model took about 00:24:01 hours on a Power Challenge SGI system. The Ⅰorder FE model of the knuckle had only 7,265nodes and it took only00:05:22hours for a baseline run.
Shape vectors, which are the most important inputs for shape optimization, were generated using‘Autodv’. The method is as follows. A group of elements are first identified