A novel methodology for Cascading Vehicle level fuel tank slosh noise performance to component level.

Slosh, a phenomenon occurring in a vehicle's tank during movement, significantly contributes to noise and vibration issues, often reaching 25dB above idle levels. Existing methods lack a standardized approach to quantify and address this dynamic, short-duration noise. This paper introduces a novel methodology to bridge this gap. This approach standardizes the generation of the slosh phenomenon by establishing vehicle-level acceleration, braking, and driving profiles. Noise and vibration data capture, along with boundary conditions and event parameters, categorizes slosh noise into Hit and Splash noise, differentiated by distinct driving profiles and frequency content. A dedicated test rig designed that replicates these conditions at the subsystem level. Vehicle speed and braking profiles are translated into rig-specific acceleration and deceleration profiles, enabling consistent data capture for correlation with vehicle-level results. Computational Fluid Dynamics (CFD) analysis utilizes these correlated boundary conditions and profiles to predict forces on the fuel tank walls. These forces inform Computer-Aided Engineering (CAE) analysis to predict noise generation, allowing for correlation between physical and predicted results and identifying any shortcomings. The successful correlation instills confidence in proposing design changes for existing fuel tanks, such as optimizing baffle designs. Six baffle designs were analyzed in CFD for forces during Hit and Splash events. The best design underwent further CAE analysis to evaluate noise reduction, resulting in a 10dB decrease in slosh noise and achieving acceptable cabin comfort levels. Additionally, this methodology facilitated the creation of design rules and target setting for NVH performance. Insights gained were applied to design a new fuel tank for a subsequent program, setting a new benchmark in the segment for reduced slosh noise. This not only improved occupant comfort but also reduced Direct Material Costs (DMC) by eliminating the need for additional baffles. This methodology offers a valuable tool for future vehicle development.