摘要
为提高谷物干燥工艺优化和装备设计水平,从干燥动力学、传热动力学、单粒谷物热湿传递、堆积谷物热湿平衡4个方面综述谷物干燥过程热湿传递研究现状。现有研究通常将谷物干燥过程有效水分扩散系数视作常数,忽略干燥过程微结构变形、微孔道坍塌导致的有效水分扩散系数随时间变化,给出随干燥时间变化的水分扩散系数计算方法,提出对于干燥条件随时间变化显著的干燥过程,可以采用机器学习方法获得水分比随时间的微分关系。分析简单几何体和复杂几何体热湿传递模型及边界方程,指出现有绝大多数单谷粒热湿传递研究未考虑谷粒内部液态水汽化的问题,因此计算结果与试验测量结果存在误差。指出结合机器学习方法,进一步提升干燥动力学建模精度与物理解释性,热量传递和水分扩散模型的准确性,及干燥工艺的智能优化是未来发展方向。
To enhance the efficiency of grain drying processes and equipment design,this article summarizes the current research status of heat and moisture transfer in grain drying processes,focusing on drying dynamics,heat transfer dynamics,single grain heat and moisture transfer,and stacked grain heat and moisture transfer.The effective moisture coefficient of the grain drying process is usually considered a constant in studies,neglecting the variation in the effective moisture diffusion coefficient with time due to deformation of the microstructure and collapse of the microchannels during the drying process.A method for calculating the moisture diffusion coefficient with drying time is presented,and it is suggested that,for drying processes with significant variations in drying conditions over time,machine learning techniques can be employed to obtain the differential relationship between moisture ratio and drying duration.I examined the heat and moisture transfer models and boundary equations of simple and complex geometric bodies and found that the vast majority of single-grain heat and moisture transfer studies did not consider the problem of liquid water vaporization inside and outside the body.The discrepancy between simulation calculation results and experimental measurement results may be due to this.Combining machine learning techniques to further enhance the measurement and modeling precision of moisture diffusion coefficient,thermal conductivity,heat transfer coefficient,and mass transfer coefficient in the drying process,as well as the precision of heat transfer and moisture diffusion models,is emphasized as the future development direction.
作者
赵青
颜建春
高辉
谢焕雄
Zhao Qing;Yan Jianchun;Gao Hui;Xie Huanxiong(Agricultural College,Yangzhou University,Yangzhou,225009,China;Nanjing Institute of Agricultural Mechanization,Ministry of Agriculture and Rural Affairs,Nanjing,210014,China)
出处
《中国农机化学报》
北大核心
2026年第1期302-311,324,共11页
Journal of Chinese Agricultural Mechanization
基金
国家重点研发计划(2023YFD2001005)。
关键词
谷物干燥
扩散系数
传热系数
热导率
热湿传递
grain drying
diffusion coefficient
heat transfer coefficient
thermal conductivity
heat and mass transfer
