A numerical investigation of electroconductive heating in solid-liquid mixtures

A mathematical model is developed to investigate the continuous-flow sterilization of solid-liquid food mixtures by electroconductive heating. Heating rates of solid and liquid phases depend on the electrical conductivities and volume fractions of the respective phases. A thermal inversion phenomenon is predicted wherein the low electrical conductivity phase which initially heats slowest, begins to heat Faster than the phase of higher electrical conductivity. Effects of fluid-solid hear transfer coefficient depends on differences in electrical conductivities of phases. When electrical conductivities are sufficiently different, poor interphase heat transfer has been shown to increase overall heating rates. (C) 1998 Elsevier Science Ltd. All rights reserved.