LS-DYNA simulations involving explosives can be modeled on several engineering levels from simple application of equivalent pressure histories via *LOAD_BLAST_ENHANCED, explicit inclusion of explosive charges using an Equations-of-State and detonation via *INITIAL_DETONATION, and detonation of explosive due to impact using *EOS_IGNITION_AND_GROWTH_OF_REACTION_IN_HE. The analyst selects the appropriate degree of model sophistication to satisfy the intended use of the model results.
Modeling explosives is analogous to material modeling: LS-DYNA offers several models and the user needs to select an appropriate model based on both applicability and the availability of appropriate input parameter data. While the selection of an appropriate material model is often driven by the availability of the input parameter data, analysts over time develop a more in depth theoretical knowledge of some material models, a personal library of material parameters and thus a preference for certain material models. However, when it comes to explosive modeling, most engineers rely solely on literature references for equations-of-state with provided data. Typically, little effort is spent on acquiring any theoretical knowledge of the equations-of-state being used, nor how the input parameters were determined.
Such cursory knowledge of explosives is often deemed acceptable, and may likely be acceptable in simulations involving fairly large standoff distances between explosive and target. However, for simulations where the explosive charge and target are not distant, or for sympathetic detonation of explosives, a more thorough knowledge of explosive modeling is required.
This class focuses on the application of LS-DYNA to modeling explosives. The modeling methods are illustrated through case studies with sufficient mathematical theory to provide the user with adequate knowledge to confidently apply the appropriate modeling method.
This training class is intended for the LS-DYNA analyst possessing a comfortable command of the LS-DYNA keywords and options associated with typical Lagrange and Multi-Material Arbitrary Lagrange Eulerian (MM-ALE) analyses. The training class will attempt to provide the analyst with the additional tools and knowledge required to model explosives for a range of applications. The typical attendee is likely to have a background in defense applications, to include protective structures and vehicle vulnerability, Homeland Defense topics, and terrorist threat mitigation techniques. The theory and illustrations portions of the class will benefit LS-DYNA users and non-LS-DYNA users alike.
Opening Remarks (Len)
Detonation Waves and Explosives (Paul)
Flyer Plate Calibration of Detasheet EOS (Len)
Impact Detonation via Ignition and Growth of Reaction in High Explosives (Len)
Driven Shocks (Paul)
TNT Equivalency (Len)
Simulation of Propellants with Application to Interior Ballistics (Paul)
Introduction to Non-Ideal and Afterburning Explosives (Len)