Previous Articles Next Articles
OUYANG Jie, HU Xiaoliang, SHEN Jian(Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, #br# Key Laboratory of Ocean Fishing Vessel and Equipment, Ministry of Agriculture,#br# National R＆D Branch Center for Aquatic Product Processing Equipment, Shanghai 200092, China)
欧阳杰，胡晓亮，沈建（中国水产科学研究院渔业机械仪器研究所，农业农村部远洋渔船与装备重点实验室，
国家水产品加工装备研发分中心，上海 200092)
Abstract:
In order to analyze the temperature distribution during radio frequency defrosting of surimi quickly, based on the dielectric properties and thermophysical parameters of pollack surimi, a numerical simulation during radio frequency defrosting of pollack surimi was carried out by COMSOL Multiphysics software, the finite element method was used to solve the electromagnetic wave dissipation and heat transfer coupling equation, and the mathematical model was verified by experiment. The results show that the temperature distribution of the upper surface, middle layer and lower surface of the surimi was the same. The numerical results agreed with the experimental results. The cold spot of each layer was always located in the center of the surimi, while the hot spot was always located in the corner area of the surimi. The temperature of the middle layer of the surimi was significantly lower than that of the upper and lower surfaces, and the temperature of the upper surface of the surimi was higher than that of the lower surface. In terms of the heating rate, the monitoring points located in the center of the surimi were the slowest, while those located in the corner area of the surimi were the fastest. Most of the measured temperature values of 9 monitoring points in the surimi sample fell on the simulated temperature change curve. By comparing the experimental value with the measured, it was shown that the COMSOL Multiphysics software could well simulate the temperature change during radio frequency heating, which could be used to predict the temperature distribution of the material.
Key words:
radio frequency,
surimi,
defrosting,
temperature,
numerical simulation,
uniformity
摘要： 为快速分析鱼糜射频解冻过程中的温度分布情况，以狭鳕鱼糜介电特性和热物性参数为基础，通过COMSOL Multiphysics软件对射频解过程进行数值模拟，以有限元方法数值求解电磁波耗散及热传递耦合方程，并对数学模型进行实验验证。结果表明：狭鳕鱼糜的上表面、中间层和下表面的温度分布高度一致，数值求解结果与实验验证结果吻合，鱼糜各层的冷点位置始终位于鱼糜中心部位，热点位置始终位于鱼糜边角区域，鱼糜中间层的温度要明显低于上、下表面，鱼糜上表面温度要高于下表面。从升温速率上看，位于鱼糜中心部位的监测点升温速度最慢，位于鱼糜边角区域的监测点升温速率最快。鱼糜样品中9个监测点的温度实测值大部分落在模拟计算的温度变化曲线上。通过试验值与测定值的比较，表明应用COMSOL Multiphysics软件可较好地模拟射频加热过程的温度变化，从而用于预测物料的温度分布。
