豆浆通电加热过程有限元解析与验证

FEM Analysis and Validation of Ohmic Heating Process of Soymilk

在通电加热加工充填豆腐的过程中,豆浆内部的温度分布对豆腐质构均匀性有很大的影响。研究豆浆通电加热过程中内部温度的分布及变化,有利于豆腐加热凝固系统的研发。对通电加热槽内豆浆的连续通电加热过程进行有限元二维模拟,并进行了实验验证。结果表明,通电加热过程中豆浆的电导率与温度之间呈线性关系;升温速率随着温度的增加而增加;豆浆内部温度分布比较均匀,靠近加热槽壁的豆浆温度较低,且随着加热时间从50 s增加到300 s,豆浆的最大温差从3℃增大到20.2℃。模拟结果和实验结果之间的均方根误差为1.86%,利用有限元模拟很好地预测了通电加热过程中豆浆内部的温度分布和变化。

In tofu making by ohmic heating,the textural uniformity of tofu is greatly influenced by the temperature distribution in soymilk.A 2-D static model was developed to visualize the change of temperature distribution in soymilk during ohmic heating process.Experimental validation of the temperature distribution obtained by mathematical modeling was performed by temperature measurement.Electrical conductivity of soymilk was correlated with temperature,uniform distribution of temperature can be obtained and heating rate is increased with the temperature.During ohmic heating process from 50 s to 300 s,the maximum temperature difference in soymilk greatly increased from 3℃ to 20.2℃.Root mean square error between experimental and simulated data was 1.86%,which indicated that numerical simulation was effective in predicting temperature distribution during ohmic heating process.