Abo Bibliothek: Guest
Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen
International Journal of Fluid Mechanics Research
ESCI SJR: 0.206 SNIP: 0.446 CiteScore™: 0.5

ISSN Druckformat: 2152-5102
ISSN Online: 2152-5110

Volumen 46, 2019 Volumen 45, 2018 Volumen 44, 2017 Volumen 43, 2016 Volumen 42, 2015 Volumen 41, 2014 Volumen 40, 2013 Volumen 39, 2012 Volumen 38, 2011 Volumen 37, 2010 Volumen 36, 2009 Volumen 35, 2008 Volumen 34, 2007 Volumen 33, 2006 Volumen 32, 2005 Volumen 31, 2004 Volumen 30, 2003 Volumen 29, 2002 Volumen 28, 2001 Volumen 27, 2000 Volumen 26, 1999 Volumen 25, 1998 Volumen 24, 1997 Volumen 23, 1996 Volumen 22, 1995

International Journal of Fluid Mechanics Research

DOI: 10.1615/InterJFluidMechRes.v25.i4-6.190
pages 662-676

Local Heat Transfer Characteristics of Horizontal in-Tube Evaporation

Samchul Ha
Home Appliance Research Lab., LG Electronics Inc., Gaeumjeong-Dong 391-2, Changwon, Kyoungnam 641-711, Korea
Arthur E. Bergles
Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York; University of Maryland, College Park, Maryland; Massachusetts Institute of Technology, Cambridge, Massachusetts, USA


Local heat transfer characteristics along the perimeter of horizontal tubes for evaporating R-12 were investigated with various parameters of different tube wall thickness, mass flux, heat flux, and quality. Plain copper tubes with outside diameter of 9.5 mm, and thicknesses of 0.8 mm and 0.4 mm were tested with indirect electrical wire heating. Circumferential and axial wall temperatures were measured, and exit flow visualization was carried out to understand the local heat transfer mechanism. Because of significant heat conduction for the present tubes, the circumferential wall superheat profile was quite flat and the wall superheat function was insensitive to the local heat transfer coefficient. A three-step model for predicting the circumferential heat transfer coefficient at the partially wetted flow is proposed. It is based upon a liquid film distribution that consists of the wavy film and the base film. The five parameters that characterize the predicted wall superheat were obtained by regression. The liquid film distribution predicted by the present model qualitatively agreed with flow visualization. Although a large variation in the circumferential heat transfer coefficient is predicted, the average heat transfer with and without considering the circumferential heat conduction was within 10% for a mass flux of 50 kg/(m2·s) and a heat flux of 5 kW/m2. The characteristics of the circumferentially averaged heat transfer coefficient were explained mainly by the liquid film wetting in separated flows.

Articles with similar content:

Transport Phenomena in Thermal Engineering. Volume 2, Vol.0, 1993, issue
Arthur E. Bergles, Samchul Ha
Critical heat flux of R134a boiling flow in the circumferentially non-uniformly heated helically coiled tubes
International Heat Transfer Conference 16, Vol.18, 2018, issue
Huaijie Yuan, Xiaojuan Niu, Liang Zhao, Chen Quan
Pressure Drop and Flow Boiling Heat Transfer of Refrigerant R-134a in Microchannel Heat Sink
International Heat Transfer Conference 15, Vol.16, 2014, issue
Vladimir V. Kuznetsov, Alisher S. Shamirzaev
Vapor Flow Effect on Falling Film Evaporation of R134a Outside Horizontal Tube Bundle
International Heat Transfer Conference 15, Vol.15, 2014, issue
Ya-Ling He, Chuang-Yao Zhao, Wentao Ji, Wen-Quan Tao, Guannan Xi
International Heat Transfer Conference 16, Vol.4, 2018, issue
Vladimir V. Kuznetsov, Alisher S. Shamirzaev