Imbibition driven by a temperature gradient

Abstract

In this work, we have theoretically studied the imbibition process in a cylindrical capillary under a constant, longitudinal temperature gradient, G. A closed-form analytical solution has been obtained and the Washburn law (valid for the isothermal case) has been found to hold for G = 0. The space and time evolution of the interface is strongly dependent on surface tension and the viscosity with temperature. By using reported data for an organic oil (squalene), we showed how imbibition can be accelerated when the temperature gradient is negative.