Dissipative behaviour of viscoelastic fluids derived from rheological constitutive equations

Abstract The dissipative source term in the temperature equation is investigated for non-isothermal flows of viscoelastic fluids. Two special cases are considered. These are the pure entropic and (internal) energy elasticity, respectively. The mechanical dissipation rate (entropy production in the system) is derived from rheological constitutive equations of the rate type. This dissipation rate is equivalent to the dissipative source term (heat production) in the temperature equation in the case of energy elasticity.