COMPUTATIONAL METHOD FOR SHAPE OPTIMIZATION.

In the direct method of shape optimum design, mesh regridding is a necessary step in order to avoid the distortion of finite element grids. The effect of internal-nodal movements on the shape design sensitivity, associated with the regridding process, has been carefully examined in this paper. It shows that the ignorance of internal-nodal movements may introduce numerical error into shape design sensitivity analysis. To take the internal-nodal movement into account, a new approach which constructs the velocity field over the element domain is presented. Although it takes more computational time, the new approach does improve the accuracy of shape design sensitivity.