Ignition and Flame Propagation in Narrow Channels of Solid Propellant

Abstract

Public reporting burden for th,5 collechon of information is esHmated to average 1 hour per response, including the time for revie,ving instruchons, searching existing data sources gatherinp and mamta.ning the data needed and complehng and reviewing the collection information. Send comments regarding this burden esHmate or anv other aspect of this collechon of information mcludmg suggestions for reducing the burden, to Deparhnent of Defense, Washington Headquarters Services, Directorate for InformaKon Operahons and Reports (0701-0188) 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-1302. Respondents should be aware that notwithstanding any other provision of law, no person shall be suWect to anv penaltx-for failing to comply with a collechon of informaHon if it does not displav a currentlvvalid 0MB conh-ol number . f . 5 PLEASE DO NOT RETURN YOIIR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) July 2003 REPORT TYPE Final TITLE AND SUBTITLE Ignition and Flame Propagation in Narrow Channels of Solid Propellant AUTHOR{S)Lang-Mann Chang and Douglas E. Kooker PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)U.S. Army Research Laboratory ATTN: AMSRL-WM-BD Aberdeen Proving Ground, MD 21005-5066 SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) DISTRIBUTION/AVAILABILITY STATEMENTApproved for public release; distribution is unlimited. ARL-TR-3011 SPONSOR/MONITOR'S ACRONYM(S) SPONSOR/MONITOR'S REPORT NUMBER(S)13. SUPPLEMENTARY NOTES ABSTRACT " " "Future direct-fire gun systems will require solid propellant at high loading density, which can be achieved with propellant in slab-type geometry such as radial discs, concentric wraps, or scrolls. Adjacent propellant slabs will form porosity as narrow sheet-like channels (with entirely different permeability than bundled sticks or cylindrical grains). Successful functioning of the charge requires rapid ignition and unimpeded flame propagation throughout this system of channels. The present investigation is concerned with characterizing the fundamental ignition and transient combustion behavior of energetic materials when packed in such configurations. A special laboratory apparatus was designed to isolate two propellant channels and allow direct comparison of the influence of variable gap width, wall composition (inert or JA2 here), and channel end closure. Diagnostics include multiple pressure time histories along each channel length and high-speed cinematography of the propagation of flame.