Simulation of Vibration Induced Fatigue of Automotive Components

Engine components and their auxiliary systems and associated fixings are subjected to loading due to both engine vibration and road loading through the chassis and mounting system. The former is subject to service load variability; the latter is considered to be random. These combined forces cause long-term fatigue in the components and their associated fixings, which is an issue throughout the automotive industry.

The aim of this research project is to create a framework for the accurate fatigue prediction of ancillary components and their fixtures when mounted on an automotive diesel engine.

The research will include the development of a powertrain model combined with a high-fidelity model of the ancillary structures susceptible to fatigue failures. This approach will be tested to ensure that it is sufficiently robust for use as a design development tool. This will require the powertrain model to be defined to take into account the characteristics of the engine and its mountings. A representative loading cycle for the components, which includes both engine and typical road induced vibrations, will be defined. The approach will enable the virtual testing of a wide a range of powertrain designs, driver styles and road characteristics, without being engine, driver or route specific.

Once these stages have been achieved, the analysis method will provide inputs to predict a realistic lifespan for various components and assist in the development of an in-service monitoring device for assessing the fatigue life of the component.