Viscous motion of particles in shock-compressed epoxy

POSTER

Abstract

Understanding the fluid response of materials at high pressure requires the characterization of transport properties such as viscosity. Here, we present an experimental measurement of the dynamic viscosity of Stycast 1266 epoxy, a common target material. The experiment was conducted at the Dynamic Compression Sector, where epoxy samples embedded with 20um tungsten particles were shock-compressed to ~4.5 GPa. High-speed radiography was used to capture the motion of the tungsten particles embedded in the epoxy. To determine the velocity behind the shock, 100nm-thick gold fiducials were placed in the epoxy. Radiographs were post-processed to determine particle position over time. Assuming that the shocked epoxy behaves as a Newtonian fluid, particle trajectories were predicted using Clift-Gauvin and Stokes drag models by iterating through various possible viscosity values; the theoretical trajectory that had the best fit to the data was used to determine the epoxy’s viscosity. Both models yielded a low particle Reynolds number (less than 1), so the Stokes drag assumption is likely appropriate.The Stokes drag model resulted in a dynamic viscosity of ~58 Pa.sec.

*This work was supported by US DOE NNSA under grant DE-NA0003914. Partial support from grants NSF PHY-2020249, DE-SC0020229 and DE-NA0004134 is also acknowledged. This work was partly performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This publication is based in part upon work performed at the Dynamic Compression Sector at the Advanced Photon Source supported by the Department of Energy, National Nuclear Security Administration, under Award Number DE-NA0002442. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. This work has been assigned an LLNL information management release number of LLNL-####-####.

Presenters

  • Anjeli Paola P Estrada Alvarez

    • University of Rochester

Authors

  • Anjeli Paola P Estrada Alvarez

    • University of Rochester

  • Afreen Syeda

    • University of Rochester

  • David B Bober

    • Lawrence Livermore Natl Lab

  • Mukul Kumar

    • Lawrence Livermore Natl Lab

  • Hussein Aluie

    • Dept. of Mechanical Engg, University of Rochester
    • Dept. of Mechanical Engg, University of Rochester. Laboratory for Laser Energetics, Rochester, NY, USA.
    • Dept. of Mechanical Eng, University of Rochester. Laboratory for Laser Energetics, Rochester, NY, USA.

  • Jessica K Shang

    • Department of Mechanical Energy, University of Rochester. Laboratory for Laser Energetics, Rochester, NY, USA.
    • Dept. of Mechanical Eng, University of Rochester. Laboratory for Laser Energetics, Rochester, NY, USA.