NUMERICAL MODELING OF THERMAL CONTACT CONDUCTANCE OF PRESSED METALLIC CONTACTS
Surface roughness is often neglected in the numerical modelling due to the complex nature and the difficulty involved in modelling the microscale features. This makes the numerical modelling unrealistic. However, surface roughness can plays a key role in heat transfer between two solids as it offers steep resistance to the flow of heat, thereby it demands for numerical modelling including the surface roughness. This study presents the structural as well as the thermal analysis of two nominally flat rough surfaces in contact using finite element method (FEM), where statistical data is used for generating roughness. Further, the influence of surface roughness, load and asperity density on contact parameters such as real contact area, mean contact gap, mean contact pressure and thermal contact conductance has been studied. Two different methods for calculating real contact area have been presented along with their accuracy in predicting the same. The main emphasis is given towards visualising the heat flow and the nonlinear behaviour of temperature distribution at the contact zone. Further, the quantitative comparison of estimated real contact area and thermal contact conductance with the analytical models has also been made. Results depict linear variation of real contact area as well as TCC with load. The real contact area is found well below 2% of nominal area under the loading range from 1 to 25 MPa.