Detail Heat and mass transfer and water absorption properties of new absorbent droplets Bibliografi Author: Warnakulasuriya, Frank Senaka Kithsiri ; Worek, W.M. (Advisor) Topik: ENGINEERING; MECHANICAL|ENGINEERING; CHEMICAL Bahasa: (EN )    ISBN: 0-599-58074-7     Penerbit: UNIVERSITY OF ILLINOIS AT CHICAGO     Tahun Terbit: 1999     Jenis: Theses - Dissertation Fulltext: 9954914.pdf (0.0B; 1 download) Abstract The performances of a model spray absorber and a solution sub-cooler; advance absorption refrigeration cycle components, were modeled, designed, constructed and tested using newly developed absorbent. To determine the heat transfer and pressure drop properties of the new absorbent, heat transfer tests in the solution sub-cooler were conducted and the results were correlated. The sub-cooler was a single pass cross-corrugated ALFA-LAVAL plate heat exchanger model PO1-VG with capacity of 14,600 W (50,000 Btu/hr). The hot side inlet temperatures varied from 55°C (130°F) to 77°C (170°F), and inlet temperature differences of 14°C (25°F), 17°C (30°F) and 20°C (35°F) were used to evaluate the performance. Reynolds number was varied from 250 to 1100, and Nusselt number from 7.4 to 15.8. The measured overall heat transfer coefficient, U, was varied from 970 W/m2°C (170 Btu/hr ft2°F) to 2270 W/m 2°C (400 Btu/hr ft2°F) and the Fanning friction factor in the absorbent side of the heat exchanger varied from 5.7 to 7.6. The correlation equations developed to predict the heat transfer and friction factors perfectly agreed with the experimental results. Those can be used to predict the performance of any solution with a Prandtl number between 82 and 174, for similar geometry heat exchangers. The mass transfer (water absorption) tests in the spray absorber were performed to determine drop formation and absorption properties of the new absorbent. The viscosity ratio, k, of this disperse/continuous phase flow is around 1300. The nozzles tested were able to produce drop sizes having a mean volumetric diameter (MVD) between 360 μm and 485 μm. The mean drop velocity was varied between 8.2 m/s (26.9 ft/s) and 16.5 m/s (54.1 ft/s). Reynolds number (continuous phase) and droplet Peclet number were varied from 10 to 1500 and 0.005 to 0.5, respectively. The best nozzle type was the Swirl-jet. Absorption rates were measured using the evaporator's power consumption. The experimental absorption ratios varied from 0.001 to 0.007. These results were then compared to the first principle analytical absorption models of Newman and Kronig-Brink. Results showed good agreement between the experimental and the Newman model results. Opini Anda Klik untuk menuliskan opini Anda tentang koleksi ini! Lihat Sejarah Pengadaan  Konversi Metadata   Kembali

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