Numerical investigation of the influence of geometric parameters on crankshaft fatigue failure using finite element analysis
The paper examines how geometric design parameters affect crankshaft fracture due to fatigue using the finite element method. It explores the influence of the fillet radius on the crankpin journal, the shape of the grooves on the splined shaft, and their interaction on the crankshaft’s fatigue behavior. Using established material traits and operating load magnitudes, a finite element analysis (FEA) computational model of the crankshaft was created, and stress simulation was performed. Following the obtained results, critical points on the crankshaft were identified, followed by fatigue analysis and lifespan evaluation. Numerical simulations showed that increasing the fillet radius on the crankpin journal significantly reduces stress concentration and boosts the crankshaft’s fatigue life. Altering the geometry of the grooves on the splined shaft redistributes stress and moderately extends its lifespan. The best results came from combining both geometric changes, demonstrating the synergistic effect of optimizing design parameters. The findings provide numerical insight into the relationship between geometric features and fatigue behaviour of crankshafts and may support further research on geometry-based design optimization.