检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:雷霞[1] 段远源[2] 史琳[2] 朱明善[2] 韩礼钟[2]
机构地区:[1]北京联合大学 [2]清华大学热能工程系,北京100084
出 处:《制冷学报》2000年第1期15-19,共5页Journal of Refrigeration
摘 要: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。To meet the restriction of the Montreal protocol,a hydrofluorocarbon (HFC) whose ozone depletion potential (ODP) value is zero to replace chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) should be looked for. The binary and/or ternary mixtures using R125 as a component are thought to be the most promising alternatives for R22. Surface tension is a basic thermophysical property,especially with respect to heat transfer through a heat exchanging surface with bubbles of fluid drops on it. The surface tension of R125 has been measured in the present work.Forty data points have been obtained by differential capillary rise method (DCRM) in the temperature range from 248 to 323 K. The temperature uncertainty is within ±10mK. The accuracy of surface tension measurements is estimated to be within ±0.1mN·m -1 .The correlation of surface tension for R125 also has been proposed
分 类 号:TB64[一般工业技术—制冷工程] TB612
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.116