MODELLING FLUID FLOW, HEAT TRANSFER AND CRYSTALLIZATION IN A SCRAPED SURFACE HEAT EXCHANGER
This paper presents numerical modelling of sucrose solutions freezing in a small and original scraped surface heat exchanger. Two approaches have been used. The first one is a 2-D transient approach considering thermodynamical equilibrium. A computational fluid dynamics (CFD) code using the Finite Element method, Comsol®, was used to solve mass, momentum and energy conservation equations. The evolution of pressure, temperature, velocity and ice fraction were determined at each point of the exchanger. The second approach is a 1-D radial transient model where ice crystal nucleation and growth kinetics are described by discrete population balance equations and coupled with CFD modelling. Evolution of population density, temperature, ice fraction and mean crystal size in the exchanger were obtained. The paper shows that the model is useful to understand the coupled effects between fluid flow, heat transfer and ice crystallization.
Benkhelifa, H., Haddad Amamou, A., Alvarez, G. and Flick, D. (2008). MODELLING FLUID FLOW, HEAT TRANSFER AND CRYSTALLIZATION IN A SCRAPED SURFACE HEAT EXCHANGER. Acta Hortic. 802, 163-170
ice crystallization, computational fluid dynamics, population balance equations, sucrose solution, transient state