Effect of electrohydrodynamic (EHD) on condensation in presence of non-condensable gas

In this paper an experimental investigation on electrohydrodynamic (EHD) augmentation of heat transfer for in-tube condensation of flowing refrigerant R-134a in presence of non-condensable gas (NC) is presented. The test section is a 1 m long counter flow heat exchanger. The refrigerant flows in the inner tube and a rod electrode placed in the tube centre. Cooling water flows through the heat exchanger annulus. The effects of electrode rode diameter, presence of non-condensable gas concentration, and application of voltage on condensation are examined. Results show a reduction in heat transfer by factor 2.1 upon presence of 20% of non-condensable gas. In the presence of the 20% of NC and 12mm electrode, a maximum heat transfer enhancement of 1.9 is experienced by applying voltage of 8 kV.

کلیدواژه ها:

Electrohydrodynamic(EHD) ، Condensation ، Non-condensable (NC) gas ، Heat transfer enhancement