Secondary effects in irreversible thermodynamics

Abstract

Linear phenomenological relations are recast to include relaxation effects. The relations are then written in a form suitable for general motion of the system and transformed to a coordinate system which is stationary relative to the observer. Generally, secondary fluxes are then observed which would be important in the fields of heat and mass transfer, for example. The Onsager relations are interpreted as reciprocal relations between the distribution functions of relaxation times. The principles on which these developments are based are that the thermodynamic properties of elements of a material are independent of the properties of neighbouring elements and also of the motion of the element in space, but may depend upon the thermodynamic history of the element.