A MODEL FOR CONDUCTION HEAT-TRANSFER TO PARTICLES IN A HOLD TUBE USING A MOVING MESH FINITE-ELEMENT METHOD

Holding mixtures of solid and liquids at a high temperature is a commo n process in sterilising food material. It is difficult to measure the temperature of a particle flowing down the holding tube. Differences in velocity and temperature between different particles must however b e estimated in order to allow prediction of process times. Experiments show that some particles may spend extended periods of time at or nea r the walls of the tube; the thermal behaviour of particles propagatin g along the wall may differ from those in the bulk. A mathematical mod el has considered this problem for the case of a rectangular shaped pa rticle sliding on the pipe wall. Analytical solutions of the conductio n equations are not available; a two-dimensional finite element progra m, using a novel dynamic moving mesh, has been developed to simulate t he moving particle. Temperature differences between wall and bulk have been shown by the model.