ListESR1 - Damping and shakedown of frictional contacts in partial slip
Recruiting Institution/Company: University of Oxford (United Kingdom)
PhD awarded by: University of Oxford (United Kingdom)
PhD Thesis: Frictional Half-Plane Contacts in Partial Slip in the Steady-State.
This project aims to understand how a number of real contact problems respond to local contact loads during cyclic loading and which combination of loads will give rise to a state of partial slip. The solutions developed allow engineers and researchers alike to assess rapidly the contact behaviour, namely the position and extent of the zones of relative cyclic motion along the interface. While knowing the slip stick pattern, by itself, does not answer the question of whether an assembly is prone to fretting fatigue or not, it enables the user to set up simple laboratory experiments in order to determine the fretting fatigue strength of the design under consideration.
Figure 1: Dovetail root joint between rotor and fan blade of a gas turbine engine with areas of attendant fretting damage.
In many fretting fatigue problems, we encounter one particular contact class, the so-called incomplete contact, which is suited for being represented by half-planes. After exploring the properties and limitations of plane elasticity and half-plane theory, we look at half-plane partial slip contact problems under different types of loading.
The project concludes with the proposal of a generalised approach to fretting fatigue strength utilising experimental results published in the literature. The test data is reinterpreted by applying the outlined asymptotic methods in order to provide generality and comparability across different geometries and loading scenarios.
Some of the work developed over the course of this project has been published in the following journal articles or book chapters:
• Andresen H., Hills D., Vázquez J. (2019b). Closed-form solutions for tilted three-part piecewise-quadratic half-plane contacts. Int. J. Mech. Sci., 150: 127–134.
• Andresen H., Hills D., Barber J., Vázquez J. (2019a). Frictional half-plane contact problems subject to alternating normal and shear loads and tension in the steady state. Int. J. Solids Struct., 168: 166–171.
• Andresen H., Hills D., Barber J., Vázquez J. (2020b). Steady state cyclic behaviour of a half-plane contact in partial slip subject to varying normal load, moment, shear load, and moderate differential bulk tension. Int. J. Solids Struct., 182: 156–161.
• Andresen H., Hills D. (2020). A review of partial slip solutions for contacts represented by half-planes including bulk tension and moments. Tribology Int., 143: 106050.
• Andresen H., Hills D., Moore M. (2020c). The steady state partial slip problem for half plane contacts subject to a constant normal load using glide dislocations. Eur. J. Mech/A Solids, 79: 103868.
• Hills D., Andresen H. (2020). Fundamentals of Elastic Contacts. In: M. Paggi and D. Hills, ed., Modeling and Simulation of Tribological Problems in Technology, 1st ed.. Springer International Publishing.
• Andresen H., Hills D., Moore M. (2020e). Representation of incomplete contact problems by half-planes. Eur. J. Mech/A Solids, 85:104138.
• Andresen H., Fleury R., Moore M., Hills D. (2021). Explicit and asymptotic solutions for incomplete half-plane contacts subject to general loading. J. Mech. Phys. Solids, 146: 104214.