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R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes

Abstract

Two-phase heat transfer coefficient characteristics of R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes are experimentally investigated. Experimental parameters include a lubricating polyol ester oil concentration varied from 0 to 4%. The test runs were done at average inlet saturated condensing temperatures of 40{sup o}C. The inlet vapor was kept at saturation (quality = 1.0). The mass fluxes were between 200 and 600 kg/m{sup 2}s, and the heat fluxes were selected to obtain a quality of 0.0 at the outlet of the test section, varying from 5 to 45 kW/m{sup 2}. The heat transfer enhancement factor varied between 1.8 and 2.4 for both microfin and cross-hatched tubes. The larger values applied for larger mass fluxes for the cross-hatched tube and smaller mass fluxes for the microfin tube. Enhancement factors increased as oil concentration increased up to oil concentrations of 2%. For higher oil concentrations the enhancement decreased especially at high mass fluxes, the cross-hatched tube being less sensitive to oil contamination. Pressure drop in the test section increased by approximately 25% as the oil concentration increased from 0 to 4%. The results from the experiments are compared with those calculated from correlations reported in the  More>>
Authors:
Infante Ferreira, C A; Nan, X; [1]  Newell, T A; Chato, J C [2] 
  1. Delft University of Technology (Netherlands). Laboratory for Refrigeration and Indoor Climate Control
  2. University of Illinois, Urbana, IL (United States). Dept. of Mechanical and Industrial Engineering
Publication Date:
Jun 01, 2003
Product Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Refrigeration; Journal Volume: 26; Journal Issue: 4; Other Information: PBD: Jun 2003
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; WORKING FLUIDS; PIPES; HEAT TRANSFER; PRESSURE DROP
OSTI ID:
20387201
Country of Origin:
United Kingdom
Language:
English
Other Identifying Numbers:
Journal ID: ISSN 0140-7007; IJRFDI; TRN: GB0350605
Submitting Site:
GB
Size:
page(s) 433-441
Announcement Date:
Oct 09, 2003

Citation Formats

Infante Ferreira, C A, Nan, X, Newell, T A, and Chato, J C. R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes. United Kingdom: N. p., 2003. Web. doi:10.1016/S0140-7007(02)00156-1.
Infante Ferreira, C A, Nan, X, Newell, T A, & Chato, J C. R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes. United Kingdom. doi:10.1016/S0140-7007(02)00156-1.
Infante Ferreira, C A, Nan, X, Newell, T A, and Chato, J C. 2003. "R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes." United Kingdom. doi:10.1016/S0140-7007(02)00156-1. https://www.osti.gov/servlets/purl/10.1016/S0140-7007(02)00156-1.
@misc{etde_20387201,
title = {R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes}
author = {Infante Ferreira, C A, Nan, X, Newell, T A, and Chato, J C}
abstractNote = {Two-phase heat transfer coefficient characteristics of R404A condensing under forced flow conditions inside smooth, microfin and cross-hatched horizontal tubes are experimentally investigated. Experimental parameters include a lubricating polyol ester oil concentration varied from 0 to 4%. The test runs were done at average inlet saturated condensing temperatures of 40{sup o}C. The inlet vapor was kept at saturation (quality = 1.0). The mass fluxes were between 200 and 600 kg/m{sup 2}s, and the heat fluxes were selected to obtain a quality of 0.0 at the outlet of the test section, varying from 5 to 45 kW/m{sup 2}. The heat transfer enhancement factor varied between 1.8 and 2.4 for both microfin and cross-hatched tubes. The larger values applied for larger mass fluxes for the cross-hatched tube and smaller mass fluxes for the microfin tube. Enhancement factors increased as oil concentration increased up to oil concentrations of 2%. For higher oil concentrations the enhancement decreased especially at high mass fluxes, the cross-hatched tube being less sensitive to oil contamination. Pressure drop in the test section increased by approximately 25% as the oil concentration increased from 0 to 4%. The results from the experiments are compared with those calculated from correlations reported in the literature. Moreover, modified correlations for the condensation heat transfer coefficient are proposed for practical applications. (author)}
doi = {10.1016/S0140-7007(02)00156-1}
journal = {International Journal of Refrigeration}
issue = {4}
volume = {26}
journal type = {AC}
place = {United Kingdom}
year = {2003}
month = {Jun}
}