Field trap effect on pool boiling enhancement in a non-uniform electric field: A numerical study

In this paper, the effect of a non-uniform electric field on pool boiling is investigated by using the pseudopotential lattice Boltzmann model and the leaky dielectric model. The focus of the study is on the field trap effect, which drives bubbles to migrate toward regions with a lower electric field intensity. Relevant results demonstrate that the non-uniform electric field effectively adjusts the distribution of dry and wet areas during boiling. Moreover, the field trap effect significantly delays the onset of film boiling by disrupting the vapor film through non-uniform electric field forces. Further, parameter analysis reveals a linear correlation between the critical heat flux and the electric capillary number (Ca_e). It is also determined that there exists an optimal electrode length that can achieve the best effect in delaying the Leidenfrost temperature (T_L). To maximize the utilization of non-uniform effects in vapor film destruction, the hydrophilic strips are introduced to inhibit bubble coalescence and can further enhance the boiling heat transfer in this way.