標題: An overview of the effect of lubricant on the heat transfer performance on conventional refrigerants and natural refrigerant R-744
作者: Wang, Chi-Chuan
Hafner, Armin
Kuo, Cheng-Shu
Hsieh, Wen-Der
機械工程學系
Department of Mechanical Engineering
關鍵字: Refrigerant;Lubricant;Heat transfer coefficient;Gas cooling;Boiling;Condensation
公開日期: 1-九月-2012
摘要: This review provides an overview of the lubricant on the heat transfer performance, including nucleate boiling, convective boiling, shell side condensation, forced convective condensation, and gas cooling, for conventional refrigerants and natural refrigerant R-744. Various parameters affecting the heat transfer coefficient subject to lubricant, such as oil concentration, heat flux, mass flux, vapor quality, geometric configuration, saturation temperature, thermodynamic and transport properties are discussed in this overview. It appears that the effect of individual parameter on the Prod. Type: FTP heat transfer coefficient may be different from studies to studies. This is associated with the complex nature of lubricant and some compound effect accompanying with the heat transport process. In this review, the authors try to summarize the general trend of the lubricant on the heat transfer coefficient, and to elaborate discrepancies of some inconsistent studies. The lubricant can, increase or impair the heat transfer performance depending on the oil concentration, surface tension, surface geometry, and the like. For the condensation, it is more well accepted that the presence of lubricant normally will impair the heat transfer performance due to deposited oil film. However, the deterioration is comparatively smaller than that in nucleate/convective boiling. For the effect of lubricant on R-744 with convective evaporation, the general behavior is in line with the convectional refrigerant. For gas cooling, the lubricant cast significant effect on heat transfer coefficient especially for a higher mass flux or at a smaller diameter tube. (c) 2012 Elsevier Ltd. All rights reserved.
URI: http://dx.doi.org/10.1016/j.rser.2012.04.054
http://hdl.handle.net/11536/20496
ISSN: 1364-0321
DOI: 10.1016/j.rser.2012.04.054
期刊: RENEWABLE & SUSTAINABLE ENERGY REVIEWS
Volume: 16
Issue: 7
起始頁: 5071
結束頁: 5086
顯示於類別:期刊論文


文件中的檔案:

  1. 000307909800064.pdf