环境实验箱气流组织与围护结构耦合传热研究

目的研究环境实验箱在升、降温过程中气流组织与围护结构的耦合传热行为,为环境实验箱制冷/加热能力的确定提供精确的设计方法。方法首先利用UC240环境实验箱搭建实验平台,测量环境箱送风口速度分布,以及升、降温过程中室内及壁面的温度曲线,然后对环境箱进行建模,以实测的送风速度、温度作为边界条件,利用CFD方法进行仿真,最后对比分析实验值与CFD仿真的结果。结果利用CFD方法计算得到的环境箱升、降温曲线与实测值吻合较好,尤其是壁面温度曲线,误差不超过4℃。送风温度可以根据蒸发器理论或加热功率和回风温度而动态地确定。结论利用CFD方法分析环境实验箱气流组织与围护结构的耦合传热是可行的,FLUENT的UDF功能可根据需要扩展,以协助设计蒸发器和控制策略。

Coupled Heat Transfer Analysis of Airflow and Enclosure Structures of Environment Test Chamber

Objective To study the coupled heat transfer of airflow and enclosure structures of environment test chamber during cooling or heating process, in order to provide an accurate method of cooling or heating capacity design for environment test chamber. Methods First, an experiment platform was established based on UC240 test chamber, airflow distribution at the outlet of environment test chamber and temperature curves inside the chamber and on the chamber wall during the cooling or heating process were measured. Then, the cooling and heating process of the chamber was calculated with CFD method, while the measured inlet air velocity and temperature was applied as the boundary conditions. Results The CFD results of temperature curves corresponded well to the experimental results, especially the curve of inner wall temperature, and the error was less than 4 ℃. The supply air temperature could be dynamically calculated according to heat exchanger theory or heating power and outlet temperature. Conclusion Calculation of coupled heat transfer of airflow and enclosure structures of environment test chamber based on CFD method was feasible and accurate. The UDF function of FLUENT could be expanded to help design heat exchanger and control system.