Numerical Considerations in the Modeling of a High Explosive Cylinder Experiment Using an ALE Continuum Mechanics Code

Marvin A Zocher,Tariq D Aslam

doi:10.3390/ma13194448

Abstract

A series of experiments involving the detonation of PBX 9501 encased in a copper cylinder are modeled with the objective of evaluating a proposed set of phenomenological parameters for the Wescott–Stewart–Davis reactive burn model. The numerical analysis is conducted using the Los Alamos continuum mechanics code FLAG. Numerical considerations pertaining to various aspects of modeling the experiments using FLAG are discussed. It is shown that use of the proposed set of phenomenological parameters results in predictions of free-surface velocity that match empirically measured velocities reasonably well.

Highlights

The high explosive (HE) cylinder test is a tool that is often used for the purpose of investigating reactive burn and the constitutive response of HE detonation products and for validating numerical models thereof
We observe that if we model the notional experiment and use full arbitrary Lagrangian–Eulerian (ALE), predicted detonation velocity approaches the accepted value from below and matches the accepted value so long as average cell size is about 160 μm or smaller
A series of experiments involving the detonation of PBX 9501 encased in a copper cylinder have been modeled with the objective of evaluating a set of phenomenological parameters for Davis-type

Summary

Introduction

The high explosive (HE) cylinder test is a tool that is often used for the purpose of investigating reactive burn and the constitutive response of HE detonation products and for validating numerical models thereof. The test normally invloves the initiation of detonation at one end of a cylinder of HE that is encased circumferentially in a thin metallic cylindrical sleeve (the metallic sleeve is open-ended). As the detonation wave propagates through the length of the cylinder, the metallic confinement expands. By carefully measuring this expansion, one may gain valuable insight into the constitutive behavior of the detonation products, and can use the measurements of cylinder expansion for quantitative model validation, comparing predicted expansion to that which is measured.

Objectives

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Discussion

Conclusion