EHD-Assisted Condensation of Refrigerant R-134a on Tube Bundles

Majid Molki, Michael Ohadi, Luciana Da Silva
2002 8th AIAA/ASME Joint Thermophysics and Heat Transfer Conference   unpublished
An experimental investigation was performed to study the electrohydrodynamic (EHD) augmentation of external condensation on tube bundles. In this research, EHD was implemented by applying a high voltage to spiral electrodes mounted on condensing tubes. The tube bundle consisted of seven enhanced tubes, housed in a shell-type aluminum test chamber. In all the experiments, the condensation fluid was refrigerant R-134a, and the tubes were cooled internally by water provided by a chiller. Six
more » ... ent tube-electrode configurations were considered and tested. The tests were conducted at the saturation temperature of 30°C, with the heat flux and applied voltage in the range of 10 -30 kW/m 2 and 0 -20 kV, respectively. The present technique was able to augment the condensation heat transfer coefficient on the average by 30% at 15 kV, while the corresponding average EHD power consumption was only 0.51%. The minimum and maximum heat transfer augmentations were 15% and 50% at 15 kV, corresponding to 0.14% and 1.46% EHD power consumptions. The condensation tests were supplemented by computer simulation of the electric field for each tube-electrode configuration to gain a better insight.
doi:10.2514/6.2002-3227 fatcat:a23d5pwzcvfgxgfb2rtuqathwq