Experimental study of heat transfer enhancement in electrohydrodynamic conduction pumping of liquid film using flush electrodes

Electrohydrodynamic conduction pumping of free surface dielectric liquid film, using flush electrodes, has been studied experimentally for various film temperatures. Volume flow rate, heat transfer and power consumption ratio and conduction pumping efficiency of free surface liquid film in different film thicknesses and temperatures have been investigated and then the best operating conditions have been presented. Also, the heat transfer coefficient on free surface liquid film passing on flush electrodes is compared with similar liquid film in absence of flush electrodes in different temperatures. Results show that as applied voltage increases, significant differences in volume flow rates have been observed by changing the temperature. Applied voltage related to the highest percentage of heat transfer coefficient enhancement demonstrates the reverse relation with temperature. Results confirm that there is a direct relationship between film thickness and the applied voltage related to the maximum heat transfer per pumps power consumption.

► Significant difference in flow rates has been observed by variation of temperature.
► The effect of temperature increase on enhancement of efficiency is considerable.
► The heat transfer coefficient in case2 increases due to vortices above electrodes.
► The optimum film thickness for heat transfer coefficient enhancement is 6 mm
► Heat transfer and power consumption ratio is decreased up to 10 kV intensively.