TIGER, A thermodynamics Equilibrium Tool for Explosives Update: Improved Solver

Hobbs, Michael Lane [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000210211982); Moffat, Harry K. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]

doi:10.2172/2585479

DOE OSTI · 2585479

TIGER, A thermodynamics Equilibrium Tool for Explosives Update: Improved Solver

Hobbs, Michael Lane [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000210211982)·Moffat, Harry K. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]

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Abstract

The thermodynamic equilibrium code known as TIGER has been in use since the 1970s and is designed to calculate the performance of energetic materials during detonation at high temperatures and pressures. The original TIGER code utilized a limited database consisting of 12 gaseous and 3 condensed constituents, which were composed of the elements carbon (C), hydrogen (H), nitrogen (N), oxygen (O), and aluminum (Al). In contrast, the more modern JCZS3 database features a significantly larger dataset, including 756 gaseous species, 189 positive and negative ions, and 496 condensed constituents derived from 62 different elements. While this expanded product species database allows for the exploration of a broader range of problems relevant to our laboratory, it also introduces challenges related to convergence, particularly when both liquid and solid species coexist under a vapor dome. In this work, we present an improved TIGER solution technique aimed at accurately determining the equilibrium state for systems that can produce a diverse array of products, including both solid and liquid condensed species. This report presents the status of the TIGER solver as of the end of FY25. Ongoing efforts are focused on enhancing the solver, and the report outlines several planned improvements. We anticipate that further developments will require additional documentation in the future.

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Hobbs, Michael Lane [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000210211982), Moffat, Harry K. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]. 2025-08-01. TIGER, A thermodynamics Equilibrium Tool for Explosives Update: Improved Solver. https://doi.org/10.2172/2585479

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