The electric field effect on the droplet collision with a heated surface in the Leidenfrost regime

In this study, the impingement of a conductive droplet on a hot wall under an electric field in the Leidenfrost regime is simulated. Apart from electrostatic equations, the governing equations are conservation equations of mass, momentum, and energy in the incompressible case. The level set method is used for interface tracking. For the appropriate application of discontinuities at the interface, the ghost fluid method is adopted. First, a sessile droplet on a superheated surface under an electric field is simulated. Simulation results are validated against the experiments. Under an electric field, an increase in the heat flux dissipated from the surface is observed for a sessile droplet. In the next step, droplet impact on a hot surface in the range of low Weber numbers (We <= 30) in the presence of an electric field is simulated. According to the results, the droplet spreading radius and contact time increase with electric field strength. In addition, applying an electric field increases the heat transfer rate and total heat removal from the surface. If the potential difference between the droplet and the surface exceeds a specific value, the Leidenfrost state is suppressed. The threshold potential difference for Leidenfrost suppression decreases with Weber number and increases with surface superheat.