Ricerca

Risultati della ricerca

  • 1. Three-dimensional full-field velocity measurements in shock compression experiments using stereo digital image correlation

    Descrizione:
    Shock compression plate impact experiments conventionally rely on point-wise velocimetry measurements based on laser-based interferometric techniques. This study presents an experimental methodology to measure the free surface full-field particle velocity in shock compression experiments using high-speed imaging and three-dimensional (3D) digital image correlation (DIC). The experimental setup has a temporal resolution of 100 ns with a spatial resolution varying from 90 to 200 μm/pixel. Experiments were conducted under three different plate impact configurations to measure spatially resolved free surface velocity and validate the experimental technique. First, a normal impact experiment was conducted on polycarbonate to measure the macroscopic full-field normal free surface velocity. Second, an isentropic compression experiment on Y-cut quartz–tungsten carbide assembly is performed to measure the particle velocity for experiments involving ramp compression waves. To explore the capability of the technique in multiaxial loading conditions, a pressure shear plate impact experiment was conducted to measure both the normal and transverse free surface velocities under combined normal and shear loading. The velocities measured in the experiments using digital image correlation are validated against previous data obtained from laser interferometry. Numerical simulations were also performed using established material models to compare and validate the experimental velocity profiles for these different impact configurations. The novel ability of the employed experimental setup to measure full-field free surface velocities with high spatial resolutions in shock compression experiments is demonstrated for the first time in this work.
    Parola chiave:
    Stereo Digital image correlation, Shock Compression, Full-field measurements, and High Speed imaging
    Soggetto:
    Applied Science and Engineering
    Creatore:
    Ravindran, Suraj , Gandhi, Vatsa , Ravichandran, Guruswami , and Joshi, Akshay
    Owner:
    n.sakthivel@jioinstitute.edu.in
    Editore:
    American Institute of Physics
    luogo:
    United States
    Lingua:
    English
    Data caricata:
    21-03-2023
    Data modificata:
    21-03-2023
    data di creazione:
    01-02-2023
    Rights Statement Tesim:
    In Copyright
    License Tesim:
    All rights reserved
    Resource Type:
    Article
    Identifier:
    10.1007/s40870-022-00359-2

  • 2. Effect of Topology on Transient Dynamic and Shock Response of Polymeric Lattice Structures

    Descrizione:
    Architected cellular materials, such as lattice structures, offer potential for tunable mechanical properties for dynamic applications of energy absorption and impact mitigation. In this work, the static and dynamic behavior of polymeric lattice structures was investigated through experiments on octet-truss, Kelvin, and cubic topologies with relative densities around 8%. Dynamic testing was conducted via direct impact experiments (25–70 m/s) with high-speed imaging coupled with digital image correlation and a polycarbonate Hopkinson pressure bar. Mechanical properties such as elastic wave speed, deformation modes, failure properties, particle velocities, and stress histories were extracted from experimental results. At low impact velocities, a transient dynamic response was observed which was composed of a compaction front initiating at the impact surface and additional deformation bands whose characteristics matched low strain-rate behavior. For higher impact velocities, shock analysis was carried out using compaction wave velocity and Eulerian Rankine–Hugoniot jump conditions with parameters determined from full-field measurements.
    Parola chiave:
    Failure, Digital image correlation, Transient dynamic, Shock, Lattice structure, and Compaction
    Soggetto:
    Applied Science and Engineering
    Creatore:
    Weeks, J. S. and Ravichandran, Guruswami
    Owner:
    n.sakthivel@jioinstitute.edu.in
    Editore:
    Springer Nature
    luogo:
    Switzerland
    Lingua:
    English
    Data caricata:
    21-03-2023
    Data modificata:
    21-03-2023
    data di creazione:
    01-12-2022
    Rights Statement Tesim:
    In Copyright
    License Tesim:
    All rights reserved
    Resource Type:
    Article
    Identifier:
    10.1007/s40870-022-00359-2