Influence of Partition Location on the Braking Performance of a Partially-Filled Tank Truck

The longitudinal load transfer encountered in a partly-filled ellipsoidal tank truck, subject to a straight-line braking maneuver, is investigated as a function of the location of partition walls, deceleration and the fill level. The response characteristics of the truck equipped with a compartmented tank are evaluated in terms of dynamic load transfer, stopping distance, braking time and time lag between the front and rear axle wheel lock-up. The braking response characteristics are derived as a function of the load shift, and number and location of partition walls. Road tests were performed on an airport fuel truck, equipped with a 3 m long tank with two movable partition walls. The simulation results derived from the test vehicle model are compared to the road test data to demonstrate the validity of the analytical model. The results show good correlation with the measured data acquired under straight-line braking maneuvers performed under different fill levels and initial speeds. The analytical and experimental results show an increase in the lag time and stopping distance with increase in the load shift caused by longitudinal fluid slosh. The study further illustrates the apparent influence of location of partitions on the braking performance, and a methodology to determine the optimal compartment sizes to minimize the magnitude of load transfer.