Integrated multibody dynamics and fatigue models for predicting the fatigue life of poly-V ribbed belts.

摘要

Belt-drives are used in many applications such as industrial machines, washing machines, and accessory drives for automobiles and other vehicles. Multibody dynamics/finite element numerical models have become an effective way to predict the dynamic response of belt-drives. In this thesis, a high fidelity numerical model was built using a multibody dynamics/finite element code to simulate a belt-drive. The belt-drive transmits power from a turbine of a Rankin cycle (that uses the exhaust waste heat of the internal combustion engine as heat source) to the crank shaft of the engine. The code uses a time-accurate explicit numerical integration technique to solve the multibody dynamics differential equations. The belt was modeled using three-node beam elements to account for the belt axial and bending stiffness/damping, while the pulleys, shafts and tensioner body were modeled as rigid bodies. The penalty technique was used to model normal contact between the belt and the pulleys. An asperity-based friction model was used to approximate Coulomb friction between the belt and the pulleys. The dynamic response predicted using the model was validated by comparing it to experimental results supplied by Cummins Inc. A parameter sensitivity study was performed to evaluate the change in response due to change in various belt-drive parameters. A fatigue model was developed to predict the belt fatigue life using output from the explicit finite element code including normal and tangential forces between the belt and the pulleys and belt tension. The belt fatigue life was evaluated for alternative belt-drive configurations in order to find the configuration with the longest life.