Theoretical Research on R245fa Condensation Heat Transfer inside a Horizontal Tube

Shengchun Liu, Yan Huo, Zhaowei Liu, Lan Li, Jinghong Ning

Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tainjin, China.

DOI: 10.4236/eng.2015.75023                

Abstract

Numerical simulation on R245fa condensation inside an inner diameter of 8 mm horizontal tube is researched in this paper. The effect of variation in velocity, condensation temperature and superheat of inlet steam and variation in cooling water temperature on heat transfer coefficient are investigated as a parametric study. Condensation process of steam has been successfully modeled by applying a user defined function (UDF) added to the commercial computational fluid dynamics (CFD) package. By analyzing the corresponding condensate contours and the curves of local heat transfer coefficient, the relationships between condensation heat transfer coefficient and various parameters of R245fa inside horizontal tube are obtained. It shows that the heat transfer coefficient increases by the increase in velocity, condensation temperature and superheat of inlet steam and the decrease in cooling water temperature. The errors between the heat transfer coefficient of simulation result and model of Wang and Shah are within ±30%. The parametric study will provide the basis for designing efficient heat exchangers of R245fa.

Keywords

Condensation Heat Transfer, R245fa, Numerical Simulation, Horizontal Tube

Conflicts of Interest

The authors declare no conflicts of interest.

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