摘要
利用FLUENT对处于空晒状态下具有不同半球发射比(!=0.04,0.06,0.08和0.10)的全玻璃真空太阳集热管管内流体的流动状态、温度分布及换热性能进行了数值模拟分析.结果表明:1空晒状态下,真空管的内管壁面温差可以达到60K,而外管壁面温差不到10K;2位于内管半径3/4处,管内空气流动速度达到最大值;3内管壁面温度随半球发射比的增大而降低,而外管壁面温度随半球发射比的增大而升高;4管内空气循环流量的最大值出现在管口处,表明散热损失主要出现在此处.
In this paper,the flow dynamics,temperature distribution and stagnation performance of all-glass evacuated solar collector tubes were simulated numerically by using ANSYS Fluent under the stagnation condition with different solar thermal emittance values(!=0.04,0.06,0.08 and 0.10).The results show that under the stagnation condition,the temperature variance on the inner tube surface can reach 60 K,whereas it is only no more than 10 K on the outer tube surface.What′s more,the temperature on the inner tube surface decreases with the increase of the solar thermal emittance values and the temperature on the outer tube surface increases with the increase of the solar thermal emittance values.The maximum radial velocity of air occurs at the three-quarters of the diameter of the inner tube.The maximum circulation flow rate is at the orifice of the tube,meaning that the maximum heat loss occurs there.
出处
《云南师范大学学报(自然科学版)》
2017年第1期6-11,共6页
Journal of Yunnan Normal University:Natural Sciences Edition
基金
国家自然科学基金资助项目(51266016
51469035)
关键词
数值模拟
半球发射比
循环流量
空晒性能
Numerical simulation
Solar thermal emittance
Circulation flow rate
Stagnation performance