A simplified method for accounting for material strength in modeling high explosive cylinder expansion tests

Here, we investigate a straightforward methodology for accounting for the plastic flow stress of copper confinement in a high explosive (HE) cylinder test using a steady supersonic flow algorithm (Andrews and Aslam, Journal of Computational Physics, 2019). We demonstrate that a simple approach of modifying momentum fluxes at the HE-confiner interface via a Young-Laplace-type law can accurately reproduce high explosive-copper cylinder expansion (CYLEX) tests modeled with the full time-dependent Preston-Tonks-Wallace (PTW) strength model (Preston, Tonks and Wallace, Journal of Applied Physics, 2003) in the LANL hydrocode FLAG (Burton, UCRL-JC-118306; CONF-9409314-1, 1994). For the same resolution, the supersonic construction is shown to be several orders of magnitude more efficient than the time-dependent code and reproduces the time-dependent simulated Photon Doppler Velocimetry (PDV) results to within 0.2%. Detailed comparisons, both with and without strength effects, are made between the steady supersonic code and the time-dependent hydrocode.