Three-dimensional numerical study of two drops impacting on a heated solid surface by smoothed particle hydrodynamics

Abstract

This paper presents a numerical study of a pair of water drops simultaneously and non-simultaneously impacting on a heated surface using smoothed particle hydrodynamics (SPH). The present SPH method is validated qualitatively and quantitively with available experiment results for the impact of single, simultaneous, and non-simultaneous drops on the solid surface. Numerical simulations are performed at the Weber number in the range of 20–117, surface temperature in the range of 25–250 °C, and pressure in the range of 1–20 bar. In the simulations, the coalescence, breakup, and evaporation of the drops are considered. After the collision of the two drops, the hydrodynamic behavior of the uprising sheet height and spreading areas are investigated by considering the horizontal and vertical distances between the two drops, Weber number, surface temperature, and elevated pressure. The numerical results indicate that the Weber number and horizontal distance significantly influence the height of the rising sheet and the spreading area. Conversely, the vertical spacing does not affect the rising sheet height or spreading area. The drop rebound height increases with the wall temperature in the film boiling regime for high boiling point liquids at atmospheric pressure. The effect of ambient pressure on drop rebound height is investigated for simultaneous and non-simultaneous impacts. According to the numerical results, the pressure increase causes a decrease in droplet rebound height.