NA Seminar: Boyan S. Lazarov (DTU)
Large-scale topology optimization
Topology optimization has gained the status of being the preferred optimization tool in the mechanical, automotive and aerospace industries. It has undergone tremendous development since its introduction in 1988, and nowadays it has spread to a number of other disciplines such as Acoustics, Optics and Material Design. The basic idea is to distribute material in a predefined domain by minimizing a selected objective and fulfilling a set of constraints. The procedure consists of repeated system analyses, gradient evaluation steps by adjoint sensitivity analysis, and design updates based on mathematical programming methods. Existence of a solution is ensured by regularization techniques.
The result of the topology optimization procedure is a bitmap image of the design. The ability of the method to modify every pixel/voxel results in a design freedom unavailable by any other alternative approach. However, this freedom comes with the requirement of using the computational power of large parallel machines. Incorporating a model accounting for exploitation and manufacturing variations in the optimization process and the high contrast between the material phases increase further the computational cost. Thus, the focus of this talk is on methods for reducing the computational complexity, ensuring manufacturability of the optimized design and efficient handling of the high contrast of the material properties. The development will be demonstrated in the design of airplane wing, compliant mechanisms, heat sinks, material microstructures for additive manufacturing, and photonic devices.