Abstract:

To study the impact of undulating road on driving stability of hazardous chemical liquid tank truck， the medium and long wave road models are constructed based on road roughness data. Taking a multi-axles liquid tank truck as the object， a vehicle dynamics model considering the tire deformation and suspension nonlinear characteristics is established. Equivalent mechanical models of the longitudinal and lateral sloshing of the liquid are established， which are coupled with the vehicle dynamics model. Kinetic parameters of the tank on different roads are obtained to excite the forced liquid sloshing model. The results show that the increase in the phase difference between the two sides of the road has an adverse effect on the lateral stability of the truck. The frequency of liquid lateral sloshing decreases with the increase of road wavelength and increases with the rise of liquid filling ratio. When the distance between the tractor saddle and the axle of the semi-trailer is an integer multiple of the road wavelength， there is significant longitudinal liquid sloshing. The oblique wave deflector can suppress lateral liquid sloshing， but the suppression effect is poor when the liquid filling ratio is low under small sloshing conditions. When the truck passes through uneven roads with a low filling ratio， increasing the vehicle speed appropriately can reduce the liquid sloshing. While the filling ratio is high， excessive vehicle speed will lead to a significant increase in liquid sloshing amplitude and wall load， reducing the driving stability of the vehicle.

Key words: liquid tank truck, road excitation, liquid sloshing, equivalent mechanical model, multi-body dynamics