روح اله فاتحی

In this paper, the effects of braking on dynamics of an articulated vehicle carrying liquid have been examined. To investigate the interaction between the fluid and the vehicle, a model of an articulated vehicle with a two-axle semitrailer has been used. The articulated tank vehicle has been modeled as a multi-body system with seven degrees of freedom (DOF) for the truck and seven DOF for the semitrailer. Also, Euler and Laplace’s equations have been used to examine the longitudinal fluid slosh. Solving Euler’s equation, the pressure exerted by the fluid to the tanker at any moment has been calculated and the resultant force at any moment has been obtained. The equations of motions are solved numerically using the Runge–Kutta method. Using the simulation results, the effects of fluid density, fill volume of the tanker, and braking intensity on dynamical parameters of the vehicle have been studied. Simulation results showed that decrease in the fill volume leads to decrease in the dynamic normal load factor of the rear axle of the semitrailer. Also, comparison of frequency response of longitudinal resultant force of the liquid and longitudinal velocity of semitrailer shows that dominant frequency of oscillation of these parameters is equal. It can be concluded that fluid sloshing is one of the main factors of oscillation of the semitrailer body and the forces between tractor and semitrailer.