Dielectrophoresis with application to boiling heat transfer in microgravity. I. Numerical analysis

• Published in: Journal of applied physics 2001-04, Vol.89 (7), p.4076-4083
• Main Authors: Snyder, Trevor J., Schneider, John B., Chung, Jacob N.
• Format: Article
• Language: English
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.1345854

This article presents a numerical analysis for the use of a dielectrophoretic (DEP) force on vapor bubbles to sustain nucleate boiling heat transfer in space where the gravity-driven buoyancy force is absent. The analytic and numerical solution procedures for the DEP force are outlined for an infinite-plate and a finite-plate electrode geometry, respectively. A simple analysis is presented that describes the limits on the magnitude of the DEP force. A comparison is made between the DEP forces produced near the edges of the finite-plate electrodes (where there is a relatively high-gradient electric field) to the forces produced between the electrodes and away from the edges (where there is a relatively low-gradient electric field). The predicted DEP forces are then used to study the effectiveness of bubble transport for both high and low electric-field gradients in microgravity. To effectively maintain boiling in space with the DEP force, a knowledge of the electric field is required which addresses both the DEP force strength and the DEP force spatial distribution in order to appropriately balance between the short-distance vapor bubble detachment needs and the long-distance bubble transport requirements.