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为适应国际上即将禁用CFC和HCFC类物质的迫切要求 ,寻找其替代物成为当务之急。R12 5是一种对臭氧层无破坏作用的新替代物 ,在目前国际上所提出的R2 2的混合工质替代物中是必不可少的组分之一。表面张力是分析计算有相变换热问题所需要的基本热物性参数。本文使用毛细管法实测了从 2 4 8K到 32 3K温度范围内 4 0组R12 5表面张力实验数据 ,温度不确定度小于± 10mK ,表面张力的不确定度为± 0 .1mN·m- 1。综合本文及文献的实验数据 ,拟合了R12 5表面张力随温度变化的关联式。
In order to meet the urgent international demand for the imminent banning of CFCs and HCFCs, finding alternatives is a top priority. R12 5 is a new alternative to the ozone layer, which is one of the indispensable components of the mixed refrigerant substitution proposed for R2 2 in the world at present. The surface tension is the basic thermophysical parameter needed to analyze and calculate the phase change heat transfer problem. In this paper, the experimental data of surface tension of 40 R12 5 in the temperature range from 240 K to 32 3 K were measured by capillary method. The temperature uncertainty was less than ± 10 mK and the surface tension uncertainty was ± 0.1 mN · m -1. Based on the experimental data of this article and the literature, the correlations of the surface tension of R12 5 with temperature are fitted.