Influence of the location of contact spots on thermal contact conductance

Abstract

Among the currently widespread fractal and stochastic models of thermal contacts, the location of contact spots formed from the interaction of roughness protrusions is not tracked in any way. Based on the results of the numerical solution of three model two-dimensional problems of thermal contact using simulation in the ANSYS finite element analysis software system, a significant effect of the location of these spots in the nominal contact area on thermal contact conductance was determined. It is shown that thermal contact conductance is not proportional to the number of actual contacts or the fraction of the actual contact area in the nominal area. As a result of the work, conclusions were drawn that even small spots of actual contact significantly change the thermal contact conductivity. Of the existing contact models, this phenomenon can be taken into account by deterministic models, since stochastic and fractal ones do not track the location of spots.