Effect of electric fields on heat transfer in liquids

Abstract

The effect of radially symmetric AC and DC electric fields on heat transfer from an electrically heated platinum wire on the insulating liquids methanol, ethanol, kerosene and silicon oil has been studied for various values of the temperature difference between the wire and the liquid. It was observed that while the AC field always enhances heat transfer, the DC field, in kerosene and silicon oil below a certain critical electric field, first causes an inhibition of heat transfer and then an increase as the field increases above the critical electric field. A reduction in heat transfer is observed in methanol, while, in the case of ethanol, the heat transfer coefficient increases, reaches a saturation value and then decreases again. An increase in heat transfer coefficient is always observed when the inclination of the cylinder containing the liquid is increased from the horizontal towards the vertical.