Modelling a Coupled Thermoelectromechanical Behaviour of Contact Elements via Fractal Surfaces

A three-dimensional coupled thermoelectromechanical model for electrical connectors is here proposed to evaluate local stress\udand temperature distributions around the contact area of electric connectors under different applied loads. A micromechanical\udnumericalmodel has been developed by merging together the contact theory approach, whichmakes use of the so-called roughness\udparameters obtained fromexperimental measurements on real contact surfaces, with the topology description of the rough surface\udvia the theory of fractal geometry. Particularly, the variation of asperities has been evaluated via the Weierstrass-Mandelbrot\udfunction. In this way the micromechanical model allowed for an upgraded contact algorithm in terms of effective contact area\udand thermal and electrical contact conductivities. Such an algorithm is subsequently implemented to construct a global model for\udperforming transient thermoelectromechanical analyses without the need of simulating roughness asperities of contact surfaces,\udso reducing the computational cost. A comparison between numerical and analytical results shows that the adopted procedure is\udsuitable to simulate the transient thermoelectromechanical response of electric connectors