Smoothed particle hydrodynamics simulation of a laser pulse impact onto a liquid metal droplet

• Published in: PloS one Vol. 13; no. 9; p. e0204125
• Main Authors: Koukouvinis, Phoevos, Kyriazis, Nikolaos, Gavaises, Manolis
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 25.09.2018; Public Library of Science (PLoS)
• Subjects: Ablation; Aeronautics; Applied physics; Cavitation; Compressibility; Computational fluid dynamics; Computer science; Computer simulation; Deformation; Droplets; Engineering and Technology; Equations of state; Finite element method; Fluid dynamics; Fluid flow; Fluid mechanics; Free surfaces; Hydraulics; Hydrodynamics; Lasers; Low pressure; Mathematical models; Mathematics; Mechanical engineering; Metals; Methods; Numerical analysis; Numerical schemes; Physical Sciences; Rarefaction; Research and Analysis Methods; Shock waves; Smooth particle hydrodynamics; Social Sciences; Tin; Transistors; Turbines; Vacuum; United Kingdom > UK
• DOI: 10.1371/journal.pone.0204125
• ISSN: 1932-6203

The impact of a laser pulse onto a liquid metal droplet is numerically investigated by utilising a weakly compressible single phase model; the thermodynamic closure is achieved by the Tait equation of state (EoS) for the liquid metal. The smoothed particle hydrodynamics (SPH) method, which has been employed in the arbitrary Lagrangian Eulerian (ALE) framework, offers numerical efficiency, compared to grid related discretization methods. The latter would require modelling not only of the liquid metal phase, but also of the vacuum, which would necessitate special numerical schemes, suitable for high density ratios. In addition, SPH-ALE allows for the easy deformation handling of the droplet, compared to interface tracking methods where strong mesh deformation and most likely degenerate cells occur. Then, the laser-induced deformation of the droplet is simulated and cavitation formation is predicted. The ablation pattern due to the emitted shock wave and the two low pressure lobes created in the middle of the droplet because of the rarefaction waves are demonstrated. The liquid metal droplet is subject to material rupture, when the shock wave, the rarefaction wave and the free surface interact. Similar patterns regarding the wave dynamics and the hollow structure have been also noticed in prior experimental studies.