Improvement of Soil Modeling in a Tire-Soil Interaction Using Finite Element Analysis and Smooth Particle Hydrodynamics
Open Access
- Author:
- Lescoe, Ryan
- Graduate Program:
- Mechanical Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- None
- Committee Members:
- Moustafa El Gindy, Thesis Advisor/Co-Advisor
Moustafa El Gindy, Thesis Advisor/Co-Advisor
Kevin L Koudela, Thesis Advisor/Co-Advisor - Keywords:
- smoothed
smooth particle hydrodynamics
FEA
finite element analysis
tire-soil interaction
soil modeling
SPH
PAM-Crash
PAM-Shock
pneumatic tire
rigid tire - Abstract:
- In recent years, the advancement of computerized modeling has allowed for the creation of extensive pneumatic tire models. These models have been used to determine many tire properties and tire-road interaction parameters which are either prohibitively expensive or unavailable with physical models. More recently, computerized modeling has been used to explore tire-soil interactions. The new parameters created by these interactions were defined for these models, but accurate soil constitutive equations were lacking. With the previous models, the soil was simulated using Finite Element Analysis (FEA) with soil material models requiring calibration and validation. Furthermore, the meshless modeling method of Smooth Particle Hydrodynamics (SPH) may be a viable approach to more accurately simulating large soil deformations and complex tire-soil interactions. For this thesis, a rigid tire model is used to perform an extensive sensitivity study on the previously used FEA soft soil (dense sand) in order to determine the importance of mesh size, soil plot size, and edge constraints. Then, parameters for SPH particles are determined for either complete or partial replacement of FEA elements in the soil model. Rolling resistance tests are conducted with a rigid tire model for different SPH and FEA/SPH soil models and compared to the previously determined best FEA soil model. Replacement of FEA elements with SPH particles is found to be the key variable as using a deeper amount of SPH particles increases rolling resistance while increasing the SPH particle density has little effect on rolling resistance. These results are then replicated using a pneumatic tire model. For further validation, pressure-sinkage tests are conducted with the FEA and SPH soils to explore the differences in the two soil modeling methods. Also, shear-displacement tests are conducted with the SPH soil—a test which cannot easily be performed with an FEA soil model. These shear tests show that the SPH soil behaves more like a clay in initial shearing and more like a sand by exhibiting increased shearing due to vertical loading. Furthermore, both the pressure-sinkage and shear-displacement tests still indicate that a larger particle density is unnecessary.