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对于种子干燥方面的研究，大多是针对其宏观传热传质即干燥动力学方面。本文采用热成象技术对单颗蚕豆种子的传热过程进行了研究，用实验求解导热方程反问题的方法计算出不同含水率下单颗种子的导热系数，对种子在非稳态下内部温度场进行了测试与分析．研究结果表明，在含水率小于 ２０％时，其导热系数随着含水率的增加而增大，当含水率大于 ２５％时则表现出较强的非均质性和非稳态性。对单颗蚕豆种子内部温度场测定而得到的种子热剖面温度分布表明，种子内部存在温度梯度其热扩散具有均匀性，同时反映出种皮传热热阻的存在。这些结果对于深入研究种子内部的传热传质机理，具有重要的实际意义。
For the study of seed drying, mostly for its macroscopic heat and mass transfer, ie dry kinetics. In this paper, thermal imaging technology was used to study the heat transfer process of single Vicia faba seeds. The inverse thermal conductivity equation was calculated experimentally to calculate the thermal conductivity of single seed under different water contents. The effects of internal temperature Field conducted a test and analysis. The results show that when the water content is less than 20%, the thermal conductivity increases with the increase of water content, while it shows strong heterogeneity and non-steady state when the water content is more than 25%. The temperature profile of the seed’s thermal profile obtained from the measurement of the internal temperature field of single broad bean seeds shows that the temperature gradient inside the seed has a uniform thermal diffusivity and reflects the existence of thermal resistance of the seed coat. These results have important practical significance for further study on the mechanism of heat and mass transfer in seeds.