不同形状果蔬速冻时辅助磁场位置的研究

Study on the Location of Magnetic Field Assisting in Freezing Vegetables with Difformity

在磁场辅助冻结果蔬时,磁场位置即预冷时间的确定至关重要。通过对蔬菜速冻过程中热量传递过程的分析,建立切成立方体的胡萝卜与马铃薯、类球形的豌豆和类圆柱的西兰花预冷过程的多维分析解模型和集中参数法模型,并进行试验验证。结果表明,多维分析解的模型可较好地预测胡萝卜、马铃薯和豌豆的预冷时间,进而确定辅助磁场的位置;以R为特征长度的集中参数模型对西兰花的预测较为准确。研究结论为不同几何体的果蔬在速冻机中的预冷时间即磁场位置的确定提供理论基础,保证试验的准确性和可重复性。

It＇s important to confirm the precooling time,namely the location of the magnetic field,which was used to assist in freezing vegetables, The models of the multidimensional analysis solution and the lumped parameter method were set up to estimate the precooling time of the carrot and potato cut into cube,near spherical pea and quasi cylindrical broccoli, and were confirmed by the experiment, The results showed that the multidimensional analysis model could estimate the time properly for the carrot,potato and pea so as to determine the positions of the magnetic field, and for the broccoli ,the lumped parameter method adopting the characteristic length R was better, This work provides the theory basis for the precooling time of the three geometric bodies in the instant freezer and ensures the accuracy and repeatability of the experiment,