Effect of heating wires with electric potential on pool-boiling heat transfer under an electric field

Abstract

In this study, we investigated the influence of heating wires with electric potential on a pool-boiling system under an electric field. We employed a numerical method that combines the pseudopotential lattice Boltzmann model, leaky dielectric model, and finite-difference model. Heating wires with different positions and electric potentials above a horizontal heater were explored. A detailed analysis of the boiling process occurring on the heater was performed at various electric-field intensities and for different boiling regimes, both with and without wires. For the pool-boiling system without heating wires, the results revealed that the critical heat flux (CHF) increased with the electric-field intensity, and the superheat required for the system to attain film boiling increased with electric field intensity. Placing heating wires on the heater surface resulted in the deterioration of heat transfer in the system without an electric field. However, the optimal distance between the heating wires and the heater remarkably promoted heat transfer during the film-boiling regime. The introduction of heating wires with electric potential into the system disrupted the original electric-field distribution, consequently impacting the boiling process and heat transfer. Compared with the system without both heating wires and an electric field, the system without heating wires exhibited a 7.9 % increase in the largest CHF at a low electric-field intensity of CaE = 0.2. However, at the same electric-field intensity, the largest CHF increased by up to 39.4 % when heating wires with an electric potential were employed. These findings provide a theoretical foundation for the practical application of effectively employing wires with electric potential to enhance boiling heat transfer.