Abstract
In this study, we have treated multi-objective optimization problem of material composition in functionally graded hollow sphere that improves strength against thermal stress and heat resistance against thermal load simultaneously. We assume that functionally graded hollow sphere has material composition that varies in radius and meridian directions so as to improve strength and heat resistance in axisymmetric thermoelastic field. Numerical solutions of thermal stress and overall heat transmission in hollow sphere are obtained by finite element analysis. We have arranged selection procedure in existing multi-objective genetic algorithms so as to find Pareto optimal front more efficiently. Pareto optimal material compositions that minimize maximum ratio of thermal stress to strength and overall heat transmission in a functionally graded hollow sphere are found by making use of present algorithm.
