4 resultados para Refrigerant
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
提出制冷剂气体水合物在纳米流体中快速生成的设想，通过HFC134a气体水合物在纳米铜流体（由0．04％的十二烷基苯磺酸钠（SDBS）水溶液和名义直径为25nm的纳米铜粒子组成）中的生成实验验证了此设想．实验结果表明，与去离子水中HFC134a气体水合物的生成过程相比，纳米铜流体中SDBS是造成HFC134a气体水合物诱导时问明显缩短的主要原因，而纳米铜粒子对诱导时间的影响不大；纳米铜流体中SDBS的乳化作用和纳米铜粒子大比表面积大大促进了HFC134a在水中的溶解；纳米铜粒子的加入明显加强了HFC134a气体水合物生成过程中的传热传质，随着纳米铜粒子数的增加，HFC134a气体水合物生成过程明显缩短．
An idea was presumed that the refrigerant gas hydrate could be formed rapidly in nanofluids, so that subsequent experiments were carried on the HFC134a gas hydrate formation process in the nanofluid comprised of 0. 04% sodium dodecylbenzenesulfonate-6solution（SDBS） and nano-copper particles of 25 nm in nominal diameter. The results indicated that, compared with the formation process of HFC134a hydrate in deionized water, the addition of 0.04 % SDBS resulted in much more reduction of induction time of HFC134a gas hydrate than the addition nano-copper did in the nanofluids. The emulation of SDBS and great specific surface of nano-copper particles greatly improved the solubility of HFC134a in water, and the formation process of HFC134a gas hydrate decreased with the mass fraction of nano-copper in nanofluid due to that the addition of nano-copper enhanced the heat and mass transfer of formation of HFC134a gas hydrate.
Resumo:
大型制冷机组部件众多，管路比较复杂，又是必须承受高压的容器，安装、调试都有严格的要求。以30HXC165A制冷机组的现场冲洗、调试为例，详细介绍了大型制冷机组在试运行之前标准的准备工作。这些工作包括吹扫、试压、排污、充注制冷剂和冲洗调试等全部过程及注意事项。本文为大型螺杆式制冷机组这种压力容器设备的运行和维护管理提供了工程实践经验。结果表明：在施工调试过程中，只有各方互相协调，并且严格按照相关文件和规范要求才能顺利完成制冷机组的安装调试，为以后的正常运行打下基础。
Strict requirements must be met during the installation and commissioning program for the large-scale chiller units since it has multitudinous components and complicated pipelines with high-pressure vessels. Preparation program was present in detail for large-scale chiller units before commissioning as the example of 30HXC165A chiller units. The total arrangement was considered about chiller units in terms of blowing, pressure trial, drainage, refrigerant filling, flushing and commissioning. The paper also provides the operation and maintenance engineering experience for large-scale screw chiller units. The results indicate that installation and commissioning can be achieved only strict abidance the related regulations demand based on harmony of all engineering participants （owners, engineering, providers etc.）. Furthermore, favorable installation and commissioning work can provide the reliable foundation of normal operation.
Resumo:
The flow behaviors of CH3CCl2F hydrate slurry with volume concentration of 10-70% were studied in a new built flow loop with a diameter of 42.0 mm and length of 30.0 m. Morphologies of the fluids from slurrylike hydrates to slushlike hydrates with increasing of hydrate volume concentration in pipeline were observed. Pressure drops in pipeline also were studied and an exceptional pressure transition zone with hydrate volume concentration between 30% and 40% was found for the first time, which can be used as a notation to judge if the pipeline runs safely or not. Fanning friction factors of the hydrate slurries with all hydrate contents tend to constants between 0.38 and 0.5, which depend on the volume concentration in slurries, when the velocity reaches 1.5 m/s. A simple relation to estimate the pressure drop of hydrate slurry in pipeline was presented and verified. Experimental results were compared to the estimated results, which showed a good agreement.
