粮堆内热湿耦合传递数值模拟与试验验证

通风过程中粮堆内热湿耦合传递对储粮安全和粮仓通风有着重要的影响。建立了机械通风冷却过程中粮堆内热湿耦合传递数学模型,在此模型的基础上用C语言编写了用户自定义源项(UDF),实现了谷粒吸附和解析水分时热量交换和水分迁移的CFD数值模拟。以某高大平房仓为例,建立了通风冷却过程中粮仓的三维物理模型;以瞬态条件下外界环境随时间变化的空气温湿度为入口边界条件,通过对比CFD数值模拟结果与实测数据,验证了粮堆内热湿耦合传递数学模型,得出通风冷却过程中粮堆内热湿耦合传递规律。

Experiment validation and numerical simulation of coupled heat and moisture transfer in stored grains

Abstract: Coupled heat and moisture transfer in stored grains during the ventilation process is very important to safety of stored grain and ventilation of the granary. A mathematical model of coupled heat and moisture transfer is presented in this paper to forest the ventilation process of the granary. Based on the model proposed, UDF sources are developed by using C language to simulate heat and moisture processes that occur in the stored grains. Taken a large warehouse as an example, a three-dimensional physical model of a real large warehouse was established. The heat and moisture transfer in a real big warehouse during the cooling ventilation, with measured temperature and moisture of air was studied by CFD simulation method and experimental method. The mathematical model proposed was validated by comparing between predicted and measured grain temperature.