Abstract
Recently, additive manufacturing methods have gained popularity for their ability to produce complex mechanical parts where conventional manufacturing methods are not suitable. Such methods not only offer a great sense of freedom to engineers but when combined with topology optimization tools can be used to simulate structures with complex shapes which satisfy the real-world loading constraints while requiring as little material as possible. Hence, combining topology optimization and additive production procedures offers a promising approach for obtaining optimized mechanical parts. This article presents a complete workflow for studying complex topology optimized parts that can be printed using additive manufacturing.
We focus on topologically optimized design approach for additive manufacturing with case studies on lightweight design of aviation safety-critical parts. The complete workflow of such a setup is discussed. The Topology Optimization of these parts has been carried out using the Solid Isotropic Material with Penalization (SIMP) algorithm [1], where a discrete optimization problem is converted to a continuous problem. The primary objective of the optimization studies is to maximize the stiffness of the chosen parts while minimizing their mass at the same time. We also investigate the effect of design constraints to account for feasible manufacturing of the part while maintaining the structural response to performance loads.
These optimized parts are then analyzed using a lumped layer approach to simulate powder bed fusion (PBF) [2] as a coupled thermal-structural analysis within ANSYS®, where the areas of maximum deformation and stress resulting from additive printing are predicted. The influence that the orientation of a part’s build direction has on the end results is investigated using a parametric study. Effect of a cartesian mesh vs a tetrahedron mesh on the results have been analyzed and best practices while working with coupled topology optimization and additive simulations have also been discussed.
