Boiling heat transfer and pressure drop of ammonia-lithium nitrate solution in a plate generator

• Published in: International journal of heat and mass transfer 2010-10, Vol.53 (21), p.4768-4779
• Main Authors: Zacarías, A., Ventas, R., Venegas, M., Lecuona, A.
• Format: Article
• Language: English
• Subjects: Ammonia-lithium nitrate solution; Applied sciences; Boiling; Boiling heat transfer; Correlation; Devices using thermal energy; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Flow rate; Fusion plate heat exchanger; Generators; Heat exchangers (included heat transformers, condensers, cooling towers); Heat transfer; Lithium; Mass transfer; Nitrates; Plate generator; Pressure drop
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2010.06.015

This paper presents the thermal and pressure-drop experimental evaluation of a fusion plate heat exchanger (PHE) during boiling conditions of a solution of lithium nitrate in ammonia. The data are representative of the working conditions of generators in single-effect absorption chillers. The solution flow rate and outlet temperature were modified in the ranges of 0.041–0.083 kg/s and 78–95 °C, respectively. Correlations for single-phase-flow heat transfer are used to characterize the boiling heat transfer. The influences of the heat flux, mass flux and exit-vapour quality are analyzed. Boiling heat-transfer coefficients and correlations for the Nusselt number are obtained. Results are compared with Cooper’s and Ayub’s correlations for boiling heat transfer. Pressure drop in the solution side was also measured and one correlation was obtained to characterize the frictional pressure drop under boiling conditions.