Development of Simulator for Microwave Thawing and Heating

目前，冷冻食品已迅速增加，并通过微波炉解冻，导致加热不均匀。在微波加热或烹饪的情况下，由于食物的热度随盐浓度而变化，因此可能发生不均匀加热。本研究中，为了控制加热不均，开发了微波加热时的温度分布预测模拟器。2003年度，开发了介电特性可选的模型食品，为了在形状不确定的状态下也能得到内部温度分布，开发了数学模型。在2004财政年度，根据2004财政年度的结果，审查了以下内容。首先，2003财年开发的数学模型假设加热和烹饪温度超过0℃，未考虑解冻过程。加热和解冻的大的区别在于， 关于我们 热量和导热系数发生很大变化，在凝固点产生潜热。在这项研究中，数学模型开发使用的外观比热模型，它不需要考虑冻结和融化层，并有可能使用一般的热传导方程。利用Hayakawa等人的预测方程估算了具有温度依赖性的物理性质。接着，利用该数学模型开发了模拟器，并利用有限元法进行了求解。在模拟器中，在个人计算机屏幕上输入以下数据，并制作计算所需的数据文件，（1）样品的形状，（2）制作元件的坐标数据，（3）解冻过程存在的信息，（4）每个元件的介电特性，（5）热物理性质值。利用该数据文件计算了温度分布，计算结果与模型食品的实测值吻合良好，证明了该模拟器的有效性。少

At present, the frozen food has been rapidly increased, and it is thawed by the microwave oven which causes uneven heating. In the case of microwave heating or cooking, since the heating-ness of food is changed with the salt concentration, the uneven heating may be occurred. In this research, in order to control the uneven heating, the simulator for predicting the temperature distribution during microwave heating of the food was developed.In the 2003 fiscal year, the model food with optional dielectric properties was developed, and the mathematical model was developed in order to obtain internal temperature distribution even in the indeterminate form state. In the 2004 fiscal year, the following was examined based on the result in 2004 fiscal year. First of all, the mathematical model developed in the 2003 fiscal year assumed heating and cooking over 0℃, and the thawing process was not considered. Large difference of heating and thawing is that the physical properties such as specific … More heat and thermal conductivity greatly changes and that the latent heat generates at freezing point. In this study, mathematical model was developed using the appearance specific heat model, which does not need to consider frozen and melting layers, and it is possible to use the general heat conduction equation. And the predictive equations of Hayakawa et al. were used in the estimation of physical property with temperature dependence.Next, the simulator was developed using this mathematical model, and was solved using finite element method. In the simulator, following data is input on the personal computer screen, and the data file necessary for the calculation is made, (1)The shape of sample, (2)The coordinate data for making the element, (3)Information of the thawing process existence, (4)The dielectric characteristic of each element, (5)The thermophysical property values. Temperature distribution was calculated using this data file.It was confirmed that this simulator was effective, because calculated result by this simulator and measured value, which was obtained using model food, agreed well. Less