The effect of venting on cookoff of a melt-castable explosive (Comp-B)

Hobbs, Michael L.; Kaneshige, Michael J.

Title: The effect of venting on cookoff of a melt-castable explosive (Comp-B)

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Abstract

Occasionally, our well-controlled cookoff experiments with Comp-B give anomalous results when venting conditions are changed. For example, a vented experiment may take longer to ignite than a sealed experiment. In the current work, we show the effect of venting on thermal ignition of Comp-B. We use Sandia’s Instrumented Thermal Ignition (SITI) experiment with various headspace volumes in both vented and sealed geometries to study ignition of Comp-B. In some of these experiments, we have used a boroscope to observe Comp-B as it melts and reacts. We propose that the mechanism for ignition involves TNT melting, dissolution of RDX, and complex bubbly liquid flow. High pressure inhibits bubble formation and flow is significantly reduced. At low pressure, a vigorous dispersed bubble flow was observed.

Authors:

Hobbs, Michael L. ^[1]; Kaneshige, Michael J. ^[1]

Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Sun Mar 01 00:00:00 EST 2015

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1184571

Report Number(s):: SAND-2014-19216J
Journal ID: ISSN 1347-9466; 540794

Grant/Contract Number:: AC04-94AL85000

Resource Type:: Accepted Manuscript

Journal Name:: Science and Technology of Energetic Materials

Additional Journal Information:: Journal Volume: 76; Journal Issue: 3; Journal ID: ISSN 1347-9466

Publisher:: Japan Explosives Society

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; Comp-B; cookoff; sealed; vented; two-phrase reactive flow

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                    Hobbs, Michael L., and Kaneshige, Michael J. The effect of venting on cookoff of a melt-castable explosive (Comp-B).  United States: N. p., 2015. 
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                    Hobbs, Michael L., & Kaneshige, Michael J. The effect of venting on cookoff of a melt-castable explosive (Comp-B).  United States.

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                    Hobbs, Michael L., and Kaneshige, Michael J. Sun .  
"The effect of venting on cookoff of a melt-castable explosive (Comp-B)".  United States.  https://www.osti.gov/servlets/purl/1184571.

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@article{osti_1184571,

  title        = {The effect of venting on cookoff of a melt-castable explosive (Comp-B)},

  author       = {Hobbs, Michael L. and Kaneshige, Michael J.},

  abstractNote = {Occasionally, our well-controlled cookoff experiments with Comp-B give anomalous results when venting conditions are changed. For example, a vented experiment may take longer to ignite than a sealed experiment. In the current work, we show the effect of venting on thermal ignition of Comp-B. We use Sandia’s Instrumented Thermal Ignition (SITI) experiment with various headspace volumes in both vented and sealed geometries to study ignition of Comp-B. In some of these experiments, we have used a boroscope to observe Comp-B as it melts and reacts. We propose that the mechanism for ignition involves TNT melting, dissolution of RDX, and complex bubbly liquid flow. High pressure inhibits bubble formation and flow is significantly reduced. At low pressure, a vigorous dispersed bubble flow was observed.},

  doi          = {},

  journal      = {Science and Technology of Energetic Materials},

  number       = 3,

  volume       = 76,

  place        = {United States},

  year         = {Sun Mar 01 00:00:00 EST 2015},

  month        = {Sun Mar 01 00:00:00 EST 2015}

}

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