柑橘地面通风贮藏库热压通风降温性能分析

An Analysis of the Cooling Performance of Thermal Driven Ventilation for Ground Ventilation Storage of Citrus

通风换气是调控柑橘贮藏库库内环境的重要手段。为了研究柑橘贮藏库通风降温性能,以湖北宜昌地区典型的柑橘地面通风贮藏库为研究对象,在瞬态热压自然通风理论的基础上,采用计算流体力学方法,建立库体的三维计算模型,采用SIMPLE算法和壁面函数法,对柑橘贮藏库的热压通风降温性能进行数值分析。分析结果表明,仿真工况下,初始时刻库内通风量达到3.5 m^3/s,通风量的工程计算结果和CFD数值模拟结果基本一致;从库内气流场和温度场分布看,库顶部分气体流动较小,热量聚集,进气口和排气口中间部分靠近墙壁的空间气体流动较少。建议在库顶安装风囱装置,增加库顶部分的通风效果,通过改变进气口、排气口的比例及位置来实现对库内流场的优化。

Ventilation is an important means to control the enuironment of citrus storehouse.In order to study the cooling performance of ventilation for citrus storage,the typical ground ventilation citrus storage in Yichang,Hubei Province was taken as the study subject.Based on the transient thermal driven natural ventilation theory,the cooling performance of thermal driven natural ventilation for citrus storage was analyzed through drawing the three dimensional model of the storage structure and choosing the SIMPLE algorithm and wall function method by using the computational fluid dynamics method.The analysis results showed that:the ventilation flux was 3.5 m 3/s under the simulation condition at the start time,the engineering calculation results of ventilation flux was basically the same as the results of CFD numerical simulation.There was less airflow at the top of the storehouse,the heat accumulated there,and the gas flow in the middle part of the inlet and the exhaust port near the wall was less.According to the distribution of gas flow field and temperature field in the storehouse,it is suggested to build a chimney to enhance the ventilation effect,thus changing the scale and position of the inlet and the exhaust port to optimize the flow field in the citrus storehouse.