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Boiling and Condensation Heat Transfer for New Refrigerants Flowing in Horizontal Tubes

新型工质在水平管内流动的沸腾与冷凝传热

基本信息

批准号：
13650230
负责人：
OHISHI Katsumi
金额：
$ 2.3万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650230/
关键词：
New Refrigerant HFE245mc New Refrigerant HFE143m Boiling Condensation Horizontal Tube Grooved Tube

项目摘要

Hydrofuluoroethers (HFEs) have recently been proposed as substitutes to conventional refrigerants including HFCs, since HFEs have Zero ozone depletion potential and also smaller global warning potential. HFE245mc and HFE143m are such substitutes to replace CFC114 especially for heat recovery heat pump systems and HFC134a for refrigerating systems respectively. In the present study, experiments were made on boiling and condensation heat transfer for HFE245mc and HFE143m flowing inside horizontal tubes.1. For each new refrigerant, there was found no peculiar difference from conventional refrigerants in the characteristics of boiling heat transfer, as results of comparisons of measured local boiling heat transfer coefficients with the authors' correlation applicable to conventional refrigerants.2. Also in condensation, the heat transfer coefficients for each new refrigerant can be satisfactorily predicted by the Hraguchi et al's correlation for conventional refrigerants.3. Comparing the values calculated from the correlations, the heat transfer coefficient for HFE245mc showed to be higher than or equal to that of CFC114 for boiling and condensation.4. Similarly, the heat transfer coefficient for HFE143m showed to be almost equal to that of HFC134a for boiling and condensation.5. From the standpoint of heat transfer, therefore, there was no problem in the use of HFE 245mc and HFE143m as the alternative refrigerants to CFC114 and HFC134a, respectively.6. In order to study the enhancement of the heat transfer coefficients, now, experiments are being on boiling and condensation for HFE245mc and HFE143m flowing inside spirally grooved tubes.

氢氟醚（HFEs）具有零臭氧消耗潜能和较小的全球警告潜能，因此最近被提议作为包括HFCs在内的常规制冷剂的替代品。HFE245mc和HFE143m分别是用于热泵系统的CFC114和用于制冷系统的HFC134a的替代品。本文对HFE 245mc和HFE 143m在水平管内的沸腾和凝结换热进行了实验研究.实验结果表明，对于每种新型制冷剂，其局部沸腾换热系数与作者提出的适用于常规制冷剂的沸腾换热系数关联式相比，没有发现与常规制冷剂有特殊的差别.此外，在冷凝，传热系数为每一个新的制冷剂可以令人满意地预测Hraguchi等人的相关性为传统的制冷剂。通过比较关联式计算的换热系数，发现HFE 245mc的沸腾换热系数大于或等于CFC 114的沸腾换热系数.类似地，对于沸腾和冷凝，HFE 143m的传热系数几乎等于HFC 134a的传热系数。因此，从热传递的观点来看，使用HFE 245mc和HFE 143m分别作为CFC 114和HFC 134a的替代制冷剂没有问题。为了研究HFE 245mc和HFE 143m在螺纹槽管内的强化传热，目前正在进行沸腾和凝结实验。