利用降压地面模拟技术,可以抑制自然对流的影响,从而通过地面试验结果还原空间密封舱内的流动换热情况.降压法的关键在于确定临界压力,使得自然对流对流动换热的影响刚好得到忽略.本文使用数值模拟方法确定临界压力比,以方腔密封舱内的流动换热情况为例,计算了不同 Gr/Re2 数和压力比下密封舱内的流动换热情况.得到了舱内气体温度分布和对流换热系数.通过比较空间情况和地面情况的计算结果,分析了自然对流给流动换热带来的影响,给出了判断临界压力的准则式,并给出了临界 Gr/Re2 数.
To study the convection heat transfer in spacecraft cabins, the lowering pressure method is usually used to suppress the effect of natural convection in terrestrial experiments. The key of lowering pressure method is to quantify a critical pressure, assuring the effect of natural convection on convection heat transfer, is exactly suppressed. In the present work, the convection heat transfer in a cubical cabin is studied numerically under various Gr/Re2 and various pressures, both in space condition and terrestrial conditions. The heat transfer coefficient and temperature distribution are obtained. Results are compared between in space condition and in terrestrial condition. The effect of pressure on suppressing the natural convection is analyzed quantitatively. The criterion formula is obtained for calculating the critical pressure in the lowering pressure method. The criterion formula for calculating the critical Gr/Re2 is also obtained.
参考文献
| [1] | RL Shannon .Thermal Scale Model Radiation-Conduction-Convection System[J].Journal of Spacecraft,1973,10(08):485-492. |
| [2] | 梁新刚;过增元;刘云龙 等.微重力条件下舱内通风换热的地面模拟技术[J].中国科学A辑,1997,27(11):1010-1013. |
| [3] | 姬朝玥,任建勋,梁新刚,陈泽敬,过增元.微重力下对流换热的地面缩比-减压模拟技术[J].清华大学学报(自然科学版),2001(02):92-94,98. |
| [4] | 张学学,刘静,蒙毅.载人飞船座舱内空气对流换热地面模拟[J].清华大学学报（自然科学版）,1999(06):67-70. |
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