Optimization of an Automotive Engine Piston System for Weight Reduction

Abstract

This thesis investigates the structural behavior and optimization potential of an automotive piston–connecting rod assembly using finite element analysis and topology optimization. After establishing the design requirements and modeling a baseline piston system, a detailed FEA was conducted under peak combustion loading to identify stress distribution, deformation, and stiffness characteristics. The results showed that the steel connecting rod and cap had significant weight-reduction potential due to their high safety margins. A density-based topology optimization was then applied with manufacturability constraints, leading to a redesigned component that preserved stiffness while removing low-stress material. The optimized design achieved a substantial 26.6% mass reduction without compromising structural integrity. Overall, the thesis demonstrates a practical and effective workflow for lightweighting reciprocating engine components to improve efficiency and performance.