ISO-XFEM FOR TOPOLOGY OPTIMIZATION OF STRUCTURES UNDER MULTIPLE LOAD CASES AND ACCELERATION LOADING

Iso-XFEM is an evolutionary based topology optimization method for generating high resolution topology optimised solutions using isolines/isosurfaces of a structural performance criterion and eXtended Finite Element Method (XFEM). The conventional approach for topology design of structures includes the use of a density based topology optimization method, such as SIMP, to find the optimal density distribution within the design domain, and thresholding the densities at an arbitrary value to obtain the design boundary. This will then require additional post-processing, such as smoothing and shape optimization, to generate a manufaturable design with smooth and clearly defined boundaries. In the proposed method, the use of XFEM with isoline/isosurface based boundary representation enables generation of topology solutions represented with smooth boundaries which can be straight away translated to a triangular surface file format, for instance STL format, in order to direct to manufacture. From analysis point of view, this allows the use of a coarser mesh during the optimization process to achieve a smooth solution, while this omits/significantly reduces the post processing required before manufacturing. The aim of this paper is to extend the Iso-XFEM method to include multiple loading cases and acceleration loading. Different 2D and 3D test cases are employed to show the effectiveness of the method.