鲢鱼肉冷冻过程中传热预测模型的建立与验证

Establishment of a Heat Transfer Model of Silver Carp Muscle during Freezing and Experimental Verification

摘要:

准确模拟冷冻过程、预测冻结时间对速冻设备的设计与控制以及保证产品质量均有重要意义。本文在鲢鱼肉热物性参数预测模型和焓模式数学模型的基础之上，采用有限差分法对平板状鲢鱼肉建立物理模型，分别预测了鲢鱼肉热中心及边界层的冷冻过程和冻结时间。实验验证表明，厚度为44 mm的鲢鱼肉的热中心和边界层的模拟温度与实验温度的平均差方和分别为1.85和1.30，冻结时间的预测相对误差为-1.64%。在此基础上，对厚度分别为24 mm和34 mm的鲢鱼肉热中心的降温过程进行了模拟，其热中心的模拟温度与实验温度的平均差方和分别为1.73和1.58。说明将热物性参数预测模型和数值模拟相结合的方法，建立的模型具有很高的拟合精度，并能实现对不同厚度鲢鱼肉的冷冻过程进行模拟，为淡水鱼冷冻加工、品质控制及设备开发提供了模拟方法。

Abstract:

Accurate simulation of the freezing process and prediction of freezing time are important for the design and control of freezing devices and assurance of product quality. Based on the prediction model of thermophysical parameters and an enthalpy-based mathematical model for silver carp muscle, a finite difference method was adopted to establish a physical model for flat silver carp muscle. The freezing process and freezing time for the thermal center and boundary layer of the silver carp muscle were also predicted. The results showed that the mean sums of squared differences between the simulated value and experimental data of the thermal center and boundary layer of the silver carp muscle with a thickness of 44 mm were 1.85 and 1.30, respectively. The relative error of the predicted freezing time versus real-time was -1.64%. Based on these results, the cooling processes for the thermal center of silver carp muscle with thicknesses of 24 mm and 34 mm were simulated, and the corresponding mean sums of squared differences between the simulated value and experimental data of the thermal center were 1.73 and 1.58, respectively. In conclusion, the model established using a combination of the prediction model of thermophysical parameters and numerical simulation showed high simulation accuracy for the freezing process of silver carp muscle with different thicknesses, providing a new simulation method for the freezing, processing, and quality control of freshwater fish and equipment design.