Evolutionary topology optimization using the extended finite element method and isolines

Abstract

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. AbstractThis study presents a new algorithm for structural topological optimization of 2D continuum structures by combining the Extended Finite Element Method (X-FEM) with an evolutionary optimization algorithm. Taking advantage of an isoline design approach for boundary representation in a fixed grid domain, X-FEM can be implemented to improve the accuracy of FE solutions on the boundary during the optimization process.Although this approach doesn't use any remeshing or moving mesh algorithms, final topologies have smooth and clearly defined boundaries which need no further interpretation. Numerical comparisons of the converged solutions with standard BESO solutions show the efficiency of the proposed method and comparison with the converged solutions using MSC NASTRAN confirms the high accuracy of this method.

Iso-Xfem for Topology Optimization of Structures Under Multiple Load Cases and Acceleration Loading

“…By employing Iso-XFEM method for topology optimization, we would expect to achieve solutions with smoother boundary than those obtained using conventional element based methods, for instance SIMP and BESO [9,11]. If a density based method, like SIMP, is employed for topology optimization, there is a need to threshold at an arbitrary density to achieve a discrete solution.…”

“…In structural optimization applications [9,11,12,13], the boundaries are defined by the intersection of the structural performance (SP) distribution with a minimum level of performance (MLP), which is typically increasing during the optimization process. Figure 1(a) shows a 2D fixed grid design domain discretized with a 30x30 mesh, where the intersection of strain energy density (SED) distribution as a structural performance criterion with a minimum level of SED gives the design boundary.…”

“…Iso-XFEM was developed in a previous study to address the issues related to the boundary representation of the topology [9,10,11]. The idea was to use a simple evolutionary based optimization algorithm (similar to BESO) while improving the boundary representation by implementing isoline/isosurface approach during the optimization.…”

A Novel Approach to Design Lesion-Specific Stents for Minimum Recoil

“…Various approaches have been proposed for TO [25][26][27][28][29][30][31][32][33], which is gaining attention in a wide variety of applications. TO based contact analysis of stent and diseased artery is a novel approach to take into account the accurate loading conditions of different plaque types to customise stent architectures according to specific lesions while maintaining vessel lumen area.…”

“…Topology optimisation results are normally meshdependent and therefore could be further investigated by employing different methods to refine the desired solution. One such recently developed method [33] is the use of extended finite element method (X-FEM), in combination with an evolutionary optimisation method that allows to obtain smooth and clearly defined structural boundaries and would potentially reduce the need to modify the TO results to obtain a manufacturable design.…”