The objective of this work is to characterize the phenomena and to identify the feasibility of the EHD technique for falling film evaporation on geometries of practical significance to industrial chillers. Single-tube experiments are conducted with refrigerants R-123 and R-134a on the outside of three commercially available vertical, electrically heated tubes. Tests are conducted with a 19 mm (3.4″) smooth tube, a 19 fpi tube, and a Turbo BIII tube. The effect of heat flux, refrigerant mass flow rate, and applied potential are investigated. Up to a 7 fold enhancement in heat transfer coefficient with R-123 and 2.1 fold with R-134a are documented. EHD power consumption in all cases is less than 0.15% of the total energy exchange rate in the test section.

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