Numerical evaluation of topologically optimized ribs for mechanical components

Abstract

Topology optimization method helps to minimize the mass or volume of the mechanical elements. In the present work, a methodology is proposed to use the topology optimization method for development of ribs like structure that add strength in the two-dimensional mechanical components. Ribs improve the stiffness significantly for the mechanical or structural components. However, the mass and the volume are also increased by adding ribs. Here a methodology is proposed to optimize the shape and size of ribs with their connections to the main component, which minimizes the overall mass. For illustration, a 2D rotary link of predefined shape and dimension are chosen, on which the ribs are added. The region of ribs is defined by initial design space of specific area such as rectangular, trapezoidal and elliptical. The density-based modified solid isotropic material with penalization approach (SIMP) is used for modeling material properties in continuous setting through interpolation and solved by optimality criteria algorithm. Minimization of compliance is chosen as the objective function, with volume fraction as a constraint ranging from 0.7 to 0.1. A MATLAB code is developed based on boundary conditions to obtain topologies at different geometrical shapes for different volume fraction. A comparison of the different shaped material domain is performed based on maximum deflection and Von-Mises stress values. The rectangular domain is found to be the best for minimum compliance and deflection, however, the trapezoidal domain is found to be the best for minimum stress levels.