Abstract
Experimental and numerical investigations have been
conducted to study the mechanisms involved in dielectric
refrigerant R-134a electrohydrodynamic (EHD) flow
boiling in a concentric horizontal flow channel.
Numerical calculations of the electric field distribution in
two-phase flow with diirerent gas-liquid distributions and
interfacial geometries in a concentric electrode
arrangement are conducted by a finite element method.
The experiments conducted are performed at inlet
qualities from 0 to 20%, mass fluxes from 100 to 500
kg/m2s, heat flux from 10kW/m2 to 20 kW/m2 and
applied voltage from 0 to 10kV. It was found that the
application of an electrohydrodynamic body force to an
R-134a evaporator can result in a significant
augmentation of heat transfer that may be partially
explained by the numerically simulated electric field
profiles near gas-liquid interfaces.