Issue:

MOCM, Number 14, Volume I

Section:

Issue No. 14 - Volume I (2008)

Abstract:

The paper presents a theoretical analysis of the effect of Joule heating on the stability of mechanical equilibrium and development of electroconvective phenomena in liquids with conductivity on the order of 10-3-10-6 S/m. Distinguishing characteristics of Joule heating of these liquids consist in the appearance of an electric force proportional to the potential difference of the fourth power, in the existence of conditions of the liquid’s dominant tendency toward electrohydrodynamic equilibrium, and development of electrothermal convection of the Joule type, which is characterized by formation of layered structures such that nonstationary wave movements are observed near the electrodes, and stationary currents like Bénard cells in the core of the flow. Depending on the heat-exchange conditions at the boundaries with the electrodes, convection may occur in a limited region of the liquid with an inversion surface for the sign of the temperature gradient, or it may encompass the whole volume if certain conditions are observed. In our view, experimental checking of obtained dependences will make it possible to confirm the physical hypotheses in relation to electric convection of the Joule type and its practical use.

Keywords:

electrohydrodynamic equilibrium, electrothermal convection, conducting liquids, Joule heating, bubbling, electric field.

Code [ID]:

MOCM200814V01S01A0021 [0001872]