CIESC Journal ›› 2025, Vol. 76 ›› Issue (3): 975-984.DOI: 10.11949/0438-1157.20240890

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

Film condensation heat transfer characteristics of R1234ze(E) on a horizontal three-dimensional finned tube

Haochen TIAN(), Zhixian MA(), Zhihao WANG   

  1. Institute of Building Energy, Dalian University of Technology, Dalian 116024, Liaoning, China
  • Received:2024-08-05 Revised:2024-09-03 Online:2025-03-28 Published:2025-03-25
  • Contact: Zhixian MA

R1234ze(E)水平三维肋管外膜状凝结特性实验研究

田浩辰(), 马志先(), 王之浩   

  1. 大连理工大学建筑能源研究所,辽宁 大连 116024
  • 通讯作者: 马志先
  • 作者简介:田浩辰(2000—),男,硕士研究生,2332547790@mail.dlut.edu.cn
  • 基金资助:
    国家自然科学基金项目(51606049)

Abstract:

The development of shell-and-tube condensers for large-scale high-efficiency heat pumps requires the film condensation heat transfer characteristics when new environmentally friendly working fluids are combined with high-efficiency condenser tubes. This study experimentally determined the film-boiling heat transfer characteristics of R1234ze(E) on the outside of a horizontal high-efficiency condensing tube and compared the differences in film-boiling characteristics between R1234ze(E) and R134a on the outside of a horizontal three-dimensional finned tube. A model for the film-boiling heat transfer coefficient of R1234ze(E) on the outside of a horizontal novel three-dimensional finned tube was established. The experimental high-efficiency condensing tube used was T2 copper with an outside diameter of 19.05 mm, a height of 0.9 mm, a fin density of 1811 fpm on the bottom and 77 fins per circumference on the top. The results show that at a condensing temperature of 38℃, the heat flux increased from 23.6 kW/m2 to 46.1 kW/m2, and the film-boiling heat transfer coefficient of R1234ze(E) on the outside of the experimental three-dimensional finned tube αo,1234ze(E) decreased from 30.9 kW/(m2·K) to 26.5 kW/(m2·K) (a decrease of 14.2%); at the same heat flux (37.6 kW/m2), the condensing temperature increased from 30℃ to 46℃, αo,1234ze(E) decreased from 33.9 to 24.3 kw/(m2·k) (a decrease of 28.3%); at the same heat flux conditions, the film-boiling heat transfer coefficient of R1234ze(E) on the outside of the experimental three-dimensional finned tube could be up 22.9 to 24.5 times that of a smooth tube; at the same condensing temperature (38℃) and heat fluxes ranging from 10 to 50 kW/m2, the film-boiling heat transfer coefficient of R1234ze(E) on the outside of the experimental three-dimensional finned tube was 1.09 to 1.25 times that of R134a. A new three-dimensional horizontal external condensation heat transfer coefficient model for R1234ze(E) is established, and the deviation between the predicted value and the experimental results is ±3.0%. The research results have reference value for the development of high efficiency shell and tube condenser for heat pump by using R1234ze(E) and new three-dimensional ribbed tube.

Key words: condensation, heat transfer, model, 3D tube, R1234ze(E)

摘要:

大型高效热泵用壳管式冷凝器开发需要新环保工质与高效冷凝管组合时的膜状凝结换热特性。实验求解了R1234ze(E)在水平高效冷凝管外膜状凝结换热特性,对比分析了其与R134a在相同水平三维肋管外的膜状凝结特性差异,并建立了R1234ze(E)水平新型三维肋管外冷凝传热系数模型。实验用高效冷凝管为T2铜管,名义外径19.05 mm,肋高0.9 mm,肋底区肋密度为1811片/m(fpm),肋顶区域单周滚扎二次肋片数为77片。结果表明:冷凝温度为38℃时,热通量从23.6增至46.1 kW/m2,R1234ze(E)在实验三维肋管外冷凝传热系数αo,R1234ze(E)从30.9降至26.5 kW/(m2·K)(下降14.2%);同热通量(37.6 kW/m2)下,冷凝温度从30升至46℃,αo,R1234ze(E)从33.9降至24.3 kW/(m2·K)(下降28.3%);同热通量下,R1234ze(E)在实验三维肋管外的冷凝传热系数可达光管的22.9~24.5倍;同冷凝温度(38℃),热通量为10~50 kW/m2时,R1234ze(E)与R134a在实验三维肋管外的冷凝传热系数比为1.09~1.25。研究结果对应用R1234ze(E)与新型三维肋管开发热泵用高效壳管式冷凝器具有参考价值。

关键词: 凝结, 传热, 模型, 三维肋管, R1234ze(E)

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