以冻库中近似大平板状的盘装柠檬片和香蕉片为实验对象，采用数值计算法模拟其冻结过程并建立描述平板状食品冻结过程传热特性的偏微分方程，通过数值计算获得柠檬片和香蕉片冻结时间的数值解，并与在-80℃、-120℃介质温度下实测的样品中心温度值比较验证．结果表明：对比原料中心温度在-20℃、-10℃、0℃、10℃、15℃五个温度点实测值与计算值，香蕉片在-80℃和-120℃冻结温度下的预测值与实测值误差绝对值的平均值分别为11.42%、11.81%，柠檬片在-80℃冻结温度下的预测值与实测值误差绝对值的平均值为6.49%，说明数值法计算结果与实测值有较好的吻合度，数值计算法在预测冻结时间方面有一定的精度和适用范围.%Taking lemon slices and banana slices placed in pan similar to flat shape frozen in refrigera⁃tion house as experimental subjects, numerical calculation method was adopted to simulate the freezing pro⁃cess, and the partial differential equation was established to describe the heat transfer characteristics of flat shape food during freezing process. Meanwhile, the comparison on center temperature of experimental subjects between numerical values and experimental values measured at-80℃and-120℃respectively was carried out. Results showed that the absolute average error between measured values and calculated values of material center temperature of banana slices and lemon slices at five points of-20℃、-10℃、0℃、10℃、15℃was 11.42%(-80℃) , 11.81%(-120℃) and 6.49%(-80℃) respectively, indicating the calculated values were in good agreement with the experimental values. Numerical calculation method had a certain degree of ac⁃curacy and application in predicting freezing time.
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