This paper presents an optimization method for optimally distributing short fibers of variable length for the reinforcement of structural components for stiffness. Unlike standard density-based and level set topology optimization methods that generally render material distributions with variable member size, the proposed method projects an explicit geometry model onto a continuous density field. The proposed method inherits the benefits of density-based topology optimization methods, namely simplified and efficient primal and sensitivity analyses on a fixed grid, fast convergence, robustness, and amenability to standard finite element methods for the analysis and to nonlinear programming algorithms for the optimization. The explicit geometry representation of the fibers provides a suitable description of the short fibers, and therefore the designs produced by the proposed method have potential for manufacturing using, for example, processing methods for the fabrication of micro-architectured materials. Examples of reinforcement distribution design for two-dimensional structures in plane stress demonstrate the method.
Topology optimization of compact wideband coaxial-to-waveguide transitions with minimum-size control
