Simulation analysis and structural optimization of double-wishbone suspension based on ANSYS

Abstract

To enhance the fatigue durability and light-weight performance of a double-wishbone independent suspension, a finite element analysis under cobblestone road excitation identifies stress concentrations at the subframe mounting hole, the upper coil spring, and the steering knuckle half-shaft root. Differentiated optimizations are performed: the subframe is treated with local geometry modification, aluminum substitution, and topology-guided lightening; the coil spring adopts a three-stage variable-pitch design; and the steering knuckle receives a local shaft diameter increase. Goodman mean stress correction quantifies the influence of material fatigue limits, while rigid‑flexible multibody dynamics and thermal‑structural coupling are employed for validation. After optimization, the subframe peak stress reduces by 46.08% with an 11.4% mass reduction and a minimum fatigue safety factor of 1.5465; the coil spring stress drops by 49.83% with a safety factor of 7.1954; the steering knuckle stress decreases by 17.78% with a safety factor of 2.6844. The system’s minimum safety factor remains above 1.5, confirming the effectiveness of the collaborative approach.