基于Phoenics的稻谷通风过程水分分布模拟初探

SIMULATION ON PADDY IN-STORE DRYING PROCESS BASED ON PHOENICS

通过改进Phoenics软件中的水分、热量和动量控制方程,并引入呼吸产生的水分源项,建立了通风过程中稻谷堆三维水分传递控制方程,可用于研究通风过程中稻谷堆内热湿传递规律。以小型测试平台数据与文献中的高大平房仓通风试验数据为基础,通过编写和导入用户自定义程序(Q1),采用有限体积元法对稻谷堆机械通风过程的水分、热量和动量方程求解。数值模拟研究结果显示,在网格数量较少的情况下,粮堆平均水分预测值仍可与实测值基本吻合,表明机械通风降水过程中稻谷的呼吸作用不可忽略。

Grain aeration is a key technique to dry stored paddy with high moisture content . In order to analyze laws of heat and moisture transfer in paddy in the grain storage system, equations of heat and moisture transfer including respiration are established in this paper using phoenics. Based on the results of the aera- tion condition in small scale storage bin and from real grain warehouse in reference, user--defined formula sources are developed and imported into the CFD software to simulate moisture transfer process. Results of the numerical simulation show that errors between predicted average moisture of stored grains and meas- ured average moisture content of stored paddy are consistent. It implies that respiration process of high moisture content paddy is important to the precision of CFD modeling.