Numerical Simulations of Thermobaric Explosions
Abstract
A Model of the energy evolution in thermobaric explosions is presented. It is based on the twophase formulation: conservation laws for the gas and particle phases along with interphase 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 fastchemistry 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 1.5g thermobaric explosions in five different chambers (volumes ranging from 6.6 to 40 liters and lengthtodiameter 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):
 UCRLCONF231319
TRN: US201215%%533
 DOE Contract Number:
 W7405ENG48
 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 twophase formulation: conservation laws for the gas and particle phases along with interphase 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 fastchemistry 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 1.5g thermobaric explosions in five different chambers (volumes ranging from 6.6 to 40 liters and lengthtodiameter 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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