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采用数值计算与差分干涉方法,对非等温竖壁的自然对流与辐射的复合换热进行了理论和实验研究,由于冷凝器水平排管的影响,竖壁温度沿高度产生周期性变化;局部对流换热系数呈起伏振荡和下降分布,水平排管的间距对局部对流换热系数有明显的影响,辐射换热的存在使得竖壁平均温度降低;在Ra=2.5×10~7-5.0×10~8,s/d=6-16范围内,辐射换热量的份额随Gr数的增大而有所增加,给出了计算非等温竖壁平均换热系数的准则关系式,为设计该类冰箱背壁散热提供了依据。
The numerical simulation and differential interference method are used to study the theoretical and experimental study on the heat transfer of natural convection and radiation of the non-isothermal vertical wall. The vertical wall temperature changes periodically along the height due to the horizontal discharge pipe of the condenser. The local convection The heat transfer coefficient fluctuated and descended, and the spacing of horizontal tubes had a significant effect on the local convective heat transfer coefficient. The existence of radiation heat transfer decreased the average temperature of vertical wall. When Ra = 2.5 × 10 ~ 7-5.0 × 10 ~ 8, s / d = 6-16, the proportion of radiative heat transfer increases with the increase of Gr, and the criterion for calculating the average heat transfer coefficient of non-isothermal vertical wall is given. Refrigerator-based refrigerator provides the basis for cooling.