Concise Mechanistic Model of Phase Change Material Solidification Kinetics

A concise power law reaction kinetic expression of reversible crystallization phase change was

presented for use in global modelling of crystallization and nucleation kinetics of solid-liquid

phase change materials (PCMs). This was developed as a closed form, wholly mechanistic

expression of phase change kinetics essential to predict coupled heat-mass latent heat evolution

in PCMs. This constituted a significant departure from the semi-empirical and

phenomenological formulations that have so far dominated PCM sciences. Notably, the

presented formulation expresses mass supersaturation as the fundamental driving force for

phase change as opposed to relying on supercooling degree or temperature rate. In contrast to

practice in the industrial crystallization process industry, it was postulated that crystal size

population balances could be neglected in PCMs used for thermal storage due to averaging

effects of crystal size population balances since the rates of latent heat evolution and heat

transport are exclusively prioritized rather than yield of a desired crystal size.