PyTOpt: A Nonlinear Topology Optimisation Program in Python

Abstract

Ever since the finite element method was introduced in the 1940’s, the behaviour of structures could more easily be predicted. Combining this with an optimisation method made it possible to minimise a structure’s weight while keeping the strength. Several topology optimisation programs have been created for this specific purpose since then. In this thesis, a topology optimisation program is implemented in Python with the method of moving asymptotes and the optimality criteria method as optimisation algorithms. By utilising previous works from universities, such as Lund University and the Technical University of Denmark, and combining the best parts a new topology optimisation program was created. The program has new functionalities not previously implemented in similar topology programs. I.e. functionalities such as the ability to utilise a variety of material models, being able to use an arbitrary design domain in 2D, body forces and asymmetrical yielding. This program also fits well in educational purposes due to its versatility. The results shows that optimality criteria method gives a better and faster result than the method of moving asymptotes. The results are also compared with commercial topology optimisation in ANSYS. The both programs gives indistinguishable results but ANSYS outperforms the thesis’s program in regards to computational time.