Fine Tuning the CJ Detonation Speed of a High Explosive products Equation of State
Abstract
For high explosive (HE) simulations, inaccuracies of a per cent or two in the detonation wave speed can result from not suficiently resolving the reaction zone width or from small inaccuracies in calibrating the products equation of state (EOS) or from variation of HE lots. More accurate detonation speeds can be obtained by ne tuning the equation of state to compensate. Here we show that two simple EOS transformations can be used to adjust the CJ detonation speed by a couple of per cent with minimal effect on the CJ release isentrope. The two transformations are (1) a shift in the energy origin and (2) a linear scaling of the speci c volume. The effectiveness of the transformations is demonstrated with simulations of the cylinder test for PBX 9502 starting with a products EOS for which the CJ detonation speed is 1 per cent too low.
 Authors:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1357103
 Report Number(s):
 LAUR1723912
 DOE Contract Number:
 AC5206NA25396
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE; high explosive; CJ detonation speed; equation of state
Citation Formats
Menikoff, Ralph. Fine Tuning the CJ Detonation Speed of a High Explosive products Equation of State. United States: N. p., 2017.
Web. doi:10.2172/1357103.
Menikoff, Ralph. Fine Tuning the CJ Detonation Speed of a High Explosive products Equation of State. United States. doi:10.2172/1357103.
Menikoff, Ralph. 2017.
"Fine Tuning the CJ Detonation Speed of a High Explosive products Equation of State". United States.
doi:10.2172/1357103. https://www.osti.gov/servlets/purl/1357103.
@article{osti_1357103,
title = {Fine Tuning the CJ Detonation Speed of a High Explosive products Equation of State},
author = {Menikoff, Ralph},
abstractNote = {For high explosive (HE) simulations, inaccuracies of a per cent or two in the detonation wave speed can result from not suficiently resolving the reaction zone width or from small inaccuracies in calibrating the products equation of state (EOS) or from variation of HE lots. More accurate detonation speeds can be obtained by ne tuning the equation of state to compensate. Here we show that two simple EOS transformations can be used to adjust the CJ detonation speed by a couple of per cent with minimal effect on the CJ release isentrope. The two transformations are (1) a shift in the energy origin and (2) a linear scaling of the speci c volume. The effectiveness of the transformations is demonstrated with simulations of the cylinder test for PBX 9502 starting with a products EOS for which the CJ detonation speed is 1 per cent too low.},
doi = {10.2172/1357103},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 5
}

Propagating detonation waves exhibit a curvature effect in which the detonation speed decreases with increasing front curvature. The curvature effect is due to the width of the wave profile. Numerically, the wave profile depends on resolution. With coarse resolution, the wave width is too large and results in a curvature effect that is too large. Consequently, the detonation speed decreases as the cell size is increased. We propose a modification to the products equation of state (EOS) to compensate for the effect of numerical resolution; i.e., to increase the CJ pressure in order that a simulation propagates a detonation wavemore »

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