DYNAMIC RESPONSE PREDICTIONS OF QUARTER-VEHICLE MODELS USING FEA AND RIGID RING TRUCK TIRE MODELS

摘要

In this paper two finite element analysis (FEA) quarter-vehicle models (QVMs) are constructed using developed nonlinear 3-and 4-groove tread FEA radial-ply truck tire models. In addition to the FEA models, a rigid ring QVM is developed to observe the dynamic response of the rigid ring tire model under the effect of the sprung mass vertical motions. The rigid ring tire model was created in the authors' previous studies. In the rigid ring QVM, the suspension characteristics are similar to that used in the FEA QVMs. Simulations are conducted using explicit FEA simulation software, PAM-SHOCK. The FEA tire model predictions of contact patch area, static vertical stiffness, first mode of free vertical vibration, and yaw oscillation frequency response are compared with measurements and found to be in good agreement. After the successful validation tasks, the FEA QVMs is subjected to a durability test on a 74 cm-long and 8.6 cm-deep water drainage ditch to observe the dynamic tire responses. Meanwhile, measurements are conducted using a tractor-semitrailer. The vertical acceleration of the front axle that moves vertically together with front tires is measured and compared with the results from the QVMs. The predicted vertical accelerations from the QVMs exhibit similar results in magnitude and trend to each other. However, the measured peak values are lower than those observed from the QVMs due to a dynamic coupling effect from roll and pitch motions. Reasonable agreement between predicted and measured vertical acceleration is observed at higher speeds because the dynamic coupling effect is less significant on the front axle of the tractor-semitrailer at higher speeds. In order to compare the dynamic tire responses of the QVMs with measured values, special test equipment similar to the QVM is required to obtain the actual dynamic tire responses in the same quarter-vehicle environment.