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复杂矩形封闭空腔中自然对流换热在工程上有着广泛的应用,诸如太阳能集热器,建筑物隔热,火焰及烟雾扩散等。本文对图2所示复杂矩形封闭空腔中自然对流换热(Ra=10~4～10~7)进行了数值研究。本文基於TEFESS 通用程序,用SIMPLE 算法和上风格式,并选取合适的初始场和松弛因子得到了形状比为1/2、几种空隙比下流场和温度场的收敛解,以及热壁上局部和平均努谢尔特数与雷莱数及空隙比的关系式。结果表明采用隔板后传热有所削弱,且隔板越厚和离热壁越远则传热效果越差。文中所得结论,不仅明确了中等雷莱数区和边界层区中有着不同的传热特性,而且对太阳能集热器,建筑物空调和隔热保温的设计都有参考价值。
Natural convection heat transfer in complex rectangular closed cavities has a wide range of engineering applications such as solar collectors, building insulation, flame and smoke diffusion. In this paper, the numerical simulation of natural convection heat transfer (Ra = 10 ~ 4 ~ 10 ~ 7) in the complex rectangular closed cavity shown in Fig.2 is carried out. In this paper, based on TEFESS general program, the SIMPLE algorithm and the upper-wind format are adopted, and the appropriate initial field and relaxation factor are selected to obtain the convergent solution of the flow field and the temperature field with shape ratio of 1/2 and several void ratios, And the relationship between the average Nusselt number and the number of Leilai and void ratio. The results show that the heat transfer is weakened after the separator is used, and the thicker the separator and the farther away from the hot wall, the worse the heat transfer effect. The conclusions drawn in this paper not only make it clear that there are different heat transfer characteristics in the middle of the Radiant Number and boundary zones, but also have reference value for the design of solar collectors, building air-conditioners and thermal insulation.