Flow boiling heat transfer of R134a and R245fa in a 2.3 mm tube

Autor(es)

Tibirica, Cristiano Bigonha ^[1] ; Ribatski, Gherhardt ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, EESC, Dept Mech Engn, BR-13566970 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER; v. 53, n. 11-12, p. 2459-2468, MAY 2010.
• Citações Web of Science: 77

Resumo

This paper presents new experimental flow boiling heat transfer results in micro-scale tubes. The experimental data were obtained in a horizontal 2.3 mm I.D stainless steel tube with heating length of 464 mm, R134a and R245fa as working fluids, mass velocities ranging from 50 to 700 kg m(-2) s(-1), heat flux from 5 to 55 kW m(-2), exit saturation temperatures of 22, 31 and 41 degrees C, and vapor qualities ranging from 0.05 to 0.99. Flow pattern characterization was also performed from images obtained by high-speed filming. Heat transfer coefficient results from 1 to 14 kW m(-2) K(-1) were measured. It was found that the heat transfer coefficient is a strong function of heat flux, mass velocity and vapor quality. The experimental data were compared against ten flow boiling predictive methods from the literature. Liu and Winterton {[}3], Zhang et al. {[}5] and Saitoh et al. {[}6] worked best for both fluids, capturing most of the experimental heat transfer trends. (C) 2010 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 05/60031-0 - Estudo teórico-experimental da ebulição convectiva de refrigerantes halogenados no interior de micro-canais
• Beneficiário: Gherhardt Ribatski
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 07/53950-5 - Estudo teórico-experimental da transferência de calor e do fluxo crítico durante a ebulição convectiva no interior de microcanais
• Beneficiário: Cristiano Bigonha Tibirica
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 06/52089-1 - Estudo teorico experimental da ebulicao convectiva de refrigerantes halogenados no interior de micro canais.
• Beneficiário: Gherhardt Ribatski
• Modalidade de apoio: Bolsas no Brasil - Jovens Pesquisadores