NONLINEAR FINITE ELEMENT MODELING AND ANALYSIS OF A TRUCK TIRE
Open Access
- Author:
- Chae, Seokyong
- Graduate Program:
- Materials
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- June 16, 2006
- Committee Members:
- Moustafa El Gindy, Committee Chair/Co-Chair
James Patrick Runt, Committee Chair/Co-Chair
Charles E Bakis, Committee Member
Ashok D Belegundu, Committee Member - Keywords:
- Truck Tire Model
FEA
Rigid Ring Tire Model
Quarter Vehicle Model
Durability Test - Abstract:
- For an efficient full vehicle model simulation, a multi-body system (MBS) simulation is frequently adopted. By conducting the MBS simulations, the dynamic and steady-state responses of the sprung mass can be shortly predicted when the vehicle runs on an irregular road surface such as step curb or pothole. A multi-body vehicle model consists of a sprung mass, simplified tire model, and suspension system to connect them. For the simplified tire model, a rigid ring tire model is mostly used due to its efficiency. The rigid ring tire model consists of a rigid ring representing the tread and the belt, elastic sidewalls, and rigid rim. Several in-plane and out-of-plane parameters need to be determined through tire tests to represent a real pneumatic tire. Physical tire tests are costly and difficult in operations. Thus, the parameters for the rigid ring tire model are alternatively predicted by conducting virtual tire tests using a finite element analysis (FEA) tire model. A nonlinear three-dimensional FEA tire model representing a truck tire, 295/75R22.5, is constructed by implementing three-layered membrane elements, hyperelastic solid elements, and beam elements. Then, the FEA tire model is validated by comparing its in-plane and out-of-plane responses with physical measurements. The virtual and physical responses show good agreements. After successful validations of the FEA tire model, virtual tire tests are conducted to predict the in-plane and out-of-plane parameters for the rigid ring tire models. The predicted parameters are implemented in the rigid ring tire model, and the model undergoes water drainage ditches 90¡Æ and 45¡Æ to the tire running direction to predict dynamic in-plane and out-of-plane tire responses at various tire loads. Vertical displacement of the tire spindle, tire contact forces, and moments are plotted and compared with those of the FEA tire model. The in-plane tire responses show good agreements between the results of the two models. On the other hand, the out-of-plane tire responses are relatively not in good agreements due to the significantly different tire contact area geometries of the two tire models on the 45¡Æ ditch. In the simulations of the FEA and rigid ring tire models, only constant vertical tire load is applied to the tire models. Additional tire load due to the vertical acceleration of the sprung mass during tire operations is not considered. Thus, a sprung mass and suspension system is assembled with the tire models to include the effect of the vertical sprung mass motion, which represents a quarter-vehicle model and a closer model to real vehicle applications. Then, the models undergo a 90¡Æ ditch at various running speeds. The vertical accelerations of the tire spindles are predicted during the ditch runs and compared with measurements to check whether or not the rigid ring tire model in the quarter-vehicle environment predicts acceptable responses. Modern high computational capability enables to establish a reliable virtual tire and quarter-vehicle model test environments. The developed quarter-vehicle model predicts not only dynamic tire responses but also sprung mass responses to irregular road surface inputs. Thus, a trustworthy quarter-vehicle model can replace the conventional field durability tests, which saves product development cost and time. In addition, virtual tests under similar conditions can be easily repeated. Higher quality products at lower cost are undoubtedly promising.