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Title: Numerical Simulations of Thermobaric Explosions

Abstract

A Model of the energy evolution in thermobaric explosions is presented. It is based on the two-phase formulation: conservation laws for the gas and particle phases along with inter-phase interaction terms. It incorporates a Combustion Model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gas dynamic fields. The Model takes into account both the afterburning of the detonation products of the booster with air, and the combustion of the fuel (Al or TNT detonation products) with air. Numerical simulations were performed for 1.5-g thermobaric explosions in five different chambers (volumes ranging from 6.6 to 40 liters and length-to-diameter ratios from 1 to 12.5). Computed pressure waveforms were very similar to measured waveforms in all cases - thereby proving that the Model correctly predicts the energy evolution in such explosions. The computed global fuel consumption {mu}(t) behaved as an exponential life function. Its derivative {dot {mu}}(t) represents the global rate of fuel consumption. It depends on the rate of turbulent mixing which controls the rate of energy release in thermobaric explosions.

Authors:
; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1046791
Report Number(s):
UCRL-CONF-231319
TRN: US201215%%533
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: Presented at: 37th International Annual Conference Energetic Materials Characterisation and Performance of Advanced Systems, Karlsruhe, Germany, Jun 26 - Jun 29, 2007
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AIR; COMBUSTION; CONSERVATION LAWS; EXPLOSIONS; FUEL CONSUMPTION; PERFORMANCE; TNT; WAVE FORMS

Citation Formats

Kuhl, A L, Bell, J B, Beckner, V E, and Khasainov, B. Numerical Simulations of Thermobaric Explosions. United States: N. p., 2007. Web.
Kuhl, A L, Bell, J B, Beckner, V E, & Khasainov, B. Numerical Simulations of Thermobaric Explosions. United States.
Kuhl, A L, Bell, J B, Beckner, V E, and Khasainov, B. Fri . "Numerical Simulations of Thermobaric Explosions". United States. doi:. https://www.osti.gov/servlets/purl/1046791.
@article{osti_1046791,
title = {Numerical Simulations of Thermobaric Explosions},
author = {Kuhl, A L and Bell, J B and Beckner, V E and Khasainov, B},
abstractNote = {A Model of the energy evolution in thermobaric explosions is presented. It is based on the two-phase formulation: conservation laws for the gas and particle phases along with inter-phase interaction terms. It incorporates a Combustion Model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gas dynamic fields. The Model takes into account both the afterburning of the detonation products of the booster with air, and the combustion of the fuel (Al or TNT detonation products) with air. Numerical simulations were performed for 1.5-g thermobaric explosions in five different chambers (volumes ranging from 6.6 to 40 liters and length-to-diameter ratios from 1 to 12.5). Computed pressure waveforms were very similar to measured waveforms in all cases - thereby proving that the Model correctly predicts the energy evolution in such explosions. The computed global fuel consumption {mu}(t) behaved as an exponential life function. Its derivative {dot {mu}}(t) represents the global rate of fuel consumption. It depends on the rate of turbulent mixing which controls the rate of energy release in thermobaric explosions.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri May 04 00:00:00 EDT 2007},
month = {Fri May 04 00:00:00 EDT 2007}
}

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