Inscrição na biblioteca: Guest
Portal Digital Begell Biblioteca digital da Begell eBooks Diários Referências e Anais Coleções de pesquisa
International Journal of Fluid Mechanics Research
ESCI SJR: 0.206 SNIP: 0.446 CiteScore™: 0.5

ISSN Imprimir: 2152-5102
ISSN On-line: 2152-5110

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

RESUMO

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:

LOCAL HEAT TRANSFER CHARACTERISTICS OF HORIZONTAL IN-TUBE EVAPORATION
Transport Phenomena in Thermal Engineering. Volume 2, Vol.0, 1993, issue
Arthur E. Bergles, Samchul Ha
R-22 Condensation in Flat Aluminum Multi-Channel Tubes
Journal of Enhanced Heat Transfer, Vol.7, 2000, issue 6
Jung-Oh Kim, Jin-Pyo Cho, Nae-Hyun Kim
CONVECTIVE BOILING HEAT TRANSFER OF WATER IN A CAPILLARY TUBE UNDER A LOW FLOW RATE CONDITION
International Heat Transfer Conference 13, Vol.0, 2006, issue
Fumito Kaminaga, Kunihito Matsumura, Sumith Baduge
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
EXPERIMENTAL INVESTIGATION OF EVAPORATIVE HEAT TRANSFER CHARACTERISTICS IN A SMALL-DIAMETER TUBE USING R-134a
Proceedings of Symposium on Energy Engineering in the 21st Century (SEE2000) Volume I-IV, Vol.0, 2000, issue
Sung Tack Ro, Min Soo Kim, Yun Wook Hwang