Thermal Rectification Due to Distortions Induced by Heat Fluxes across Contacts between Smooth Surfaces

Abstract

Predictions have been derived for the distribution of true contact area and the associated constriction resistance for a pressed contact between two surfaces which are flat when isothermal but become bowed in the presence of heat fluxes across the contact. Induced thermal strains of the interfacial surfaces can lead to the preferential passage of heat in one direction across the contact. Experimental measurements of the thermal resistance of a contact between a specimen of En58B stainless steel and one of commercially-pure aluminium corroborate this theory. The study has identified some of the mistakes which can be made unconsciously, and remain unrecognized subsequently, in using standard measuring techniques for the thermal resistance of a pressed contact.