Abstract
High Energy Density (HED) Physics study matter under extreme states of pressure and temperature present in planetary interiors, astrophysical jets or fusion devices. Exciting data was obtained from single shot experiments recreating these conditions in laboratory using energetic laser/ion-beam drivers. In recent years, driven by the development towards high-repetition-rate drivers, collecting HED related data at a greater frequency is now within reach. For high-repetition-rate operation, liquid droplets can be used to provide a continuously refreshing target. However, one must make sure that extreme conditions produced during the preceding interaction and target debris do not degrade the next target. This is a challenging computational fluid dynamics (CFD) problem that needs to model not only the initial dynamics of the heated droplet, but also the late time interaction with the following droplets. Here, the code PISALE is used to study the case of a 1) liquid hydrogen and 2) liquid water droplet heated by an x-ray free electron laser. After showing high-resolution 2D results for a single heated droplet, we investigate in a 3D simulation the impact of the laser-droplet interaction on two subsequent droplets and compare it to available experimental data. We study the effect of surface tension on the subsequent droplets' deformation.
*This work is supported by the National Science Foundation, the U. S. Department of Energy, Office of Science, under Fusion Energy Sciences Research Division Award Number FWP100182.The PISALE code is supported by the National Science Foundation, under Office of Advanced Cyber Infrastructure Award Number 2005259, the U. S. Department of Energy, Office of Science, under Fusion Energy Sciences Research Division Award Number DE-SC0021374, and the Office of Naval Research, under ONR MURI Award Number N00014- 20-1-2682. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231 using NERSC awards ERCAP0020882 and ERCAP00208