Enhanced pool boiling of propane on horizontal U-shaped tubes in a large-scale confined space. (January 2022)

• Record Type: Journal Article
• Authors: Tian, Zhen; Wang, Feng; Gu, Bo; Zhang, Yuan; Gao, Wenzhong
• Is Part Of: International journal of refrigeration. Volume 133(2022)
• Page Start: 19
• Page End: 29
• Publication Date: 2022-01
• Subjects: Propane -- Pool boiling -- Heat transfer coefficient -- Fin-enhanced tube -- Large-scale confined space -- Correlation comparison; Propane -- Ébullition libre -- Coefficient de transfert de chaleur -- Tube amélioré par des ailettes -- Espace restreint à grande échelle -- Comparaison des corrélations; Refrigeration and refrigerating machinery -- Periodicals; 621.56
• DOI: 10.1016/j.ijrefrig.2021.09.026
• Languages: English
• ISSNs: 0140-7007

Abstract

Highlights: The experimental data of propane pool boiling on a fin-enhanced tube was obtained. The heat transfer coefficients demonstrated increasing with heat flux and saturation temperature. The enhancement factors were found in the range of 1.25∼2.28. Optimum correlations were validated to predict the experimental data within 11.48%. Abstract: This paper aims to experimentally investigate the heat transfer characteristics of pool boiling on horizontal U-shaped tubes in a large-scale confined space. The saturation temperature ranges from 20 to 40°C and the heat flux varies from 2.5 to 10.5 kWm −2 . Two types of tubes with an outside diameter of 19.05 mm are tested: a smooth tube and a fin-enhanced tube with 0.4 mm fin height, 1220 fpm (fins per meter) and a 0.12 mm fin gap. The tubes are made of titanium with a length of 1165 mm. In case of pool boiling, the heat transfer coefficient for the tested tubes increases with increasing saturation temperature and heat flux. The fin-enhanced tube facilitates the bubble nucleation with the heat transfer coefficient enhancement factor varying in the range of 1.25∼2.28. Furthermore, the experimental heat transfer coefficients are compared with four correlations obtained in the open literature. R-J correlation and Copper correlation are found to be the optimum correlation for the smooth tube and the enhanced tube with the mean relative error of 10.93% and 11.48%, respectively. Findings from this study can supply a fundamental basis for validation and improvement propane heat transfer performances for the intermediate fluid vaporizer (IFV) engineering design.