NUMERICAL SIMULATION OF PULSED ELECTRIC FIELDS (PEF) PROCESSING FOR CHAMBER DESIGN AND OPTIMISATION

The pulsed electric fields technology (PEF) is a highly effective method for liquid food preservation at low or moderate temperatures. One key component of this technology is the treatment chamber, in which the food is exposed to a pulsed electric field. The electric field strength and the temperature distribution in the treatment chamber have been identified as the key processing parameters affecting treatment efficacy and the sensorial characteristic of the food. A computational fluid dynamics (CFD) model, describing the stationary flow pattern, the electric field and the temperature distributions in a pilot-scale treatment chamber with co-linear configuration of the electrodes, was developed and validated by means of temperature mapping studies using fibre optic probes. The impact of different treatment chamber designs on process uniformity was simulated. All simulations were performed with the commercial software package COMSOL Multiphysics ™ (Comsol AB, Stockholm, Sweden), which is based on the Finite Element Method (FEM). NOTATION