The relationship between the mean radial electrohydrodynamic (EHD) pressure and the rate of the axial momentum flux and its influence on heat transfer enhancement and pressure drop in EHD-enhanced convective boiling of R-134a in a horizontal smooth tube was investigated in detail. A simple theory, which included the characteristics of two-phase flow, was developed to determine the mean radial EHD pressure. It was shown that the amount of heat transfer enhancement and the pressure drop penalty were dependent upon the size of the mean radial EHD pressure relative to the rate of the axial momentum flux. The influence of the mass flux, change in quality, and saturation temperature on the mean radial EHD pressure relative to the rate of the axial momentum flux was also studied. This study has provided a greater understanding of EHD enhancement of the convective boiling heat transfer. [S0022-1481(00)01802-8]

Issue Section:
Boiling and Condensation
Keywords:
convection, boiling, electrohydrodynamics, two-phase flow, Electric Fields, Enhancement, Heat Transfer, Phase Change, Two-Phase
Topics:
Boiling, Electrohydrodynamics, Flow (Dynamics), Heat transfer, Momentum, Pressure, Pressure drop, Electrodes, Electric fields, Two-phase flow, Heat transfer coefficients, Temperature, Fluids
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