A simplified framework for sensitivity analysis of energy dissipation in bogie suspension systems

Heavy-haul railways face significant energy losses due to motion resistance, particularly from wheel-rail interactions and suspension dynamics. This study investigates the influence of suspension parameters on energy dissipation through a combined sensitivity analysis employing multibody simulation. A meter-gauge freight wagon was modeled in SIMPACK® using a Box-Behnken experimental design to evaluate five key parameters: primary suspension stiffness (longitudinal/lateral), secondary suspension stiffness, wedge height, and wedge friction. Simulations covered multiple curve radii (300–2000 m) and speeds (35–65 km/h), compared against a 40 km of a heavy-haul line. Results demonstrated that primary suspension longitudinal stiffness and wedge height dominated energy dissipation. In tight curves (≤500 m), the influence of suspension stiffness became more pronounced due to increased flange contact, whereas in smoother curves, wedge interactions dominated the dynamic behavior The wedge height-friction interaction surpassed individual parameter effects, highlighting the need for integrated maintenance. The 300 m curve simplification exhibited a high correlation (>0.93) with full-track energy dissipation across all speed ranges, allowing for accurate energy estimation via reduced-section simulations, with a mean error under 5%. These findings provide a methodology for optimizing suspension systems and simplifying energy assessments in heavy-haul operations. The validated 300 m curve equivalency enhances computational efficiency for network-scale analyses without compromising accuracy. Additionally, the parameter sensitivity findings support targeted maintenance strategies aimed at improving energy efficiency.