Numerical analysis of a pressure wave generated in a liquid Pb upon impact of the pneumatic pistons and its interaction with a free surface has been performed for the geometry and parameters of the plasma compression system prototype constructed by General Fusion Inc. Stress wave developing in the hammer–anvil piston assembly is first simulated using high-fidelity structural mechanics research code, then propagated through the liquid Pb with several solvers within OpenFOAM® software and also with nonlinear acoustics in-house code based on the Westervelt equation. In the current system, a pressure wave transmitted into the liquid Pb is characterized by a complex temporal double peak structure and strong spatial amplitude variation. An imprint of discrete pulses remains detectable during the entire propagation of the combined wave. An excellent agreement between the results produced with different numerical codes is obtained. Nonlinear effects associated with equation of state are found to be significant at impact velocities of 50 m/s, while at lower velocities of 10 m/s the difference between the results obtained with linear and nonlinear equations of state is negligible. Liquid–gas interface dynamics during the compression process of a spherical gas cavity is captured very well by the compressibleInterFoam within OpenFOAM.
V. Suponitsky, D. Plant, E. J. Avital and A. Munjiza, 2017. Pressure Wave in Liquid Generated by Pneumatic Pistons and Its Interaction with a Free Surface. International Journal of Applied Mechanics, volume 9, issue 3. doi: 10.1142/S1758825117500375
This is a pre-copyedited, author-produced version of an article accepted for publication in the International Journal of Applied Mechanics following peer review.
© 2017 International Journal of Applied Mechanics and Imperial College Press.