高压脉冲电场处理室多物理场仿真研究

高压脉冲电场杀菌技术是一种新型的高效非热杀菌技术。高压脉冲电场处理室是杀菌处理的关键部件,其结构形式决定了处理室内部电场分布、温度场分布、流场分布,并影响杀菌处理的效果,同时电场强度和温度分布影响被处理食品的口味。以不同结构共场杀菌处理室为研究对象,利用COMSOL Multiphysics软件对共场杀菌处理室内部电场分布、温度场分布、流场分布对处理参数均匀性的影响进行了仿真。仿真结果表明,绝缘体无内嵌的处理室电场强度分布不均匀,对绝缘体倒椭圆角后的处理室可有效改善电场及流场分布,进而有效降低局部温升,改善处理效果。

A Simulation Study of Multilevel Physical Field on Pulsed Electric Fields

The pulsed electric fields technology (PEF)is a highly effective method for liquid food preser-vation 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.In this paper,with developed different isolator geometries co-linear PEF treatment chamber as research object,all simulations were performed with the commercial software package COMSOL Multiphysics which analysised the stationary flow pattern,the electric field and the temperature distri-butions.Simulation results show that non-uniform electric field strength at the standard chamber,but elliptical isolator geometry chamber can effectively improve the electric field and flow field distribution,thus effectively reduce the temperature rise.It is concluded that elliptical embedded co-field sterilization treatment chamber is more suitable aiming at the pilot-scale and the industrialized PEF sterilization system with high performance re-quirements for its excellent coupled-field characteristics.