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Indexed by:Journal Papers

Date of Publication:2020-04-01

Journal:INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID

Included Journals:EI、SCIE

Volume:112

Page Number:303-313

ISSN No.:0140-7007

Key Words:R124-NMP mixture; Heat transfer; Mass transfer; Bubble absorber; Dimensionless correlations

Abstract:An experimental study on heat and mass transfer characteristics of R124-NMP in a vertical glass bubble absorber has been conducted under operating conditions of air-cooled absorption system. The key operation parameters, solution volumetric flow rate, temperature and mass fraction at the absorption tube entrance, vapor volumetric flow rate, orifice diameter and absorption pressure, are converted into dimensionless numbers. A sensitive study of the key operation parameters on overall heat and mass transfer coefficients and two-phase mass transfer coefficient has been performed. The overall heat and mass transfer coefficients and two-phase mass transfer coefficient increase as Re-v and absorption pressure increase and decrease as orifice diameter increases. The overall heat transfer coefficient increases as Re-s increases and decreases as solution temperature and mass fraction increase. This trend is reversed for overall mass transfer coefficient. The increase of solution inlet mass fraction can improve the two-phase mass transfer coefficient while the solution inlet temperature affects the two-phase mass transfer coefficient slightly. On the basis of the experimental data, dimensionless empirical correlations for overall and two-phase Sherwood numbers are proposed with error bands of +/- 10% to calculate the volumetric mass transfer coefficient for R124-NMP bubble absorption process in a vertical bubble absorber. (C) 2020 Elsevier Ltd and IIR. All rights reserved.