Performance assessment of meshed and meshless numerical methods in physics-based modeling of tire-soil interaction

The study of tire-soil interaction is very complex due to the non-linear and granular nature of the soil. Further, the strength of the soil also varies based on the applied normal load, slip ratio, moisture content, and stress history. This study proposes a physics-based methodology for modeling tire-soil interaction using different numerical approaches. The relative compatibility, stability, and accuracy of a meshed method (Coupled Eulerian-Lagrangian-CEL) are compared with a particle-based method (Smooth particle hydrodynamics-SPH) for predicting plain rigid tire performance in off-road conditions. For the numerical simulation, triaxial test data of non-cohesive soil (Norfolk Sandy Loam-NSL) is used to parameterize the Drucker-Prager soil constitutive material model. A rigid tire model and load cases, the same as the experimental study, are used for numerical simulations. Net traction predicted using the SPH method provided a relatively better correlation with experimental data compared to the CEL method. The difference in net traction prediction between both methods is observed mainly due to different numerical and contact formulations. Further, a parametric study is also performed to understand the sensitivity of net traction to the tire dimensions. This study develops a better understanding of current numerical modeling deformable soil which could be used for design optimization of off-road tires.