Transient heat conduction through a substrate of brine-spongy ice

An analytical model for heat conduction through brine-spongy ice is developed. This model fills a gap in knowledge related to transient heat conduction to a two-phase substrate which is crucial for modeling transient icing and deicing of cold surfaces in contact with salt water. The core of the model is based on the phase change of pure ice and brine pockets trapped in the structure of spongy ice. Freezing of brine pockets causes the release of the latent heat of fusion that is considered as the source of heat generation distributed throughout the brine-spongy ice. A nonlinear partial differential equation and a number of equations of state for ice, brine, and brine-spongy ice create governing equations of heat transfer through brine-spongy ice. A standard numerical scheme solves the set of equations in various initial conditions. The variation of temperature, volume fraction of brine and salinity of brine pockets are calculated numerically. Experimental samples of brine-spongy ice are examined under transient conditions and their surface temperatures are captured using an infrared thermal camera. The numerical results, which are for various overall salinities, are closely aligned with the measured surface temperatures.