ISSN:0010-2202    

DOI:10.1080/00102207308952358

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

An analytic model for the vapor-phase combustion of single metal particles is proposed. The condensation of vaporized oxides on the droplet surface and the motion of condensed oxides are properly accounted for. Three modes of vapor-phase combustion are possible depending on the direction of motion of the condensed oxides formed at the flame. Additional solutions, valid in dilute or enriched atmospheres, are obtained by allowing the flame temperature to decrease or increase, respectively. Flammability limits are also determined. Sample solutions are obtained for the combustion of Al and Be with O2. It is shown that the mass burning rate and the flame stand-off distance are substantially increased by allowing for surface condensation. Be is found to burn much slower than Al, in addition to its tendency to accumulate substantial condensed oxides on the droplet surface. When results of the model are compared with available experimental observation, the agreement is reasonable, both qualitatively and quantitatively.

ISSN:0010-2202    

DOI:10.1080/00102207308952359

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

Pressurization with nitrogen has been studied as a technique for suppressing fires in confined spaces. Liquid hydrocarbon-air fires of various sizes in a gastight experimental chamber were extinguished in approximately 30 seconds by increasing the total pressure of the enclosure from l atm. to 1.35 ± 0.03 atm. The post-fire atmospheres were found to contain sufficient oxygen for support of normal human activity, while the buildup of hazardous combustion products was well below established safety levels.

ISSN:0010-2202    

DOI:10.1080/00102207308952360

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

An experimental and analytical study of chemi-ionization processes in reacting methane/air mixtures was carried out at temperatures up to 2000 °K. Using the reflected shock region as a homogeneous reaction zone, Langmuir probe measurements were performed in a conventional shock tube to determine positive ion concentrations and their induction times. The results are analyzed by means of a numerical study using an ionization mechanism incorporated into recently established methane oxidation mechanisms, and the calculated and experimental ion concentrations are comparable primarily at higher temperatures. Various ionization mechanisms are discussed. The ion-concentrations are compared to those obtained from flame studies at similar conditions, and although ion concentrations in homogeneous systems are higher, the ion production rates are found to be comparable.

ISSN:0010-2202    

DOI:10.1080/00102207308952361

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor

摘要:

A brief investigation of the combustion characteristics of a solid propellant containing a binder which chars, as opposed to melting or volatizing, has been made. The burning rate of the propellant with the charring binder was significantly higher than similar propellants containing non-charring binders. High speed motion pictures of the burning propellant showed that the aluminum burned on the regressing surface, rather than a short distance from it as is typical with composite propellants.

ISSN:0010-2202    

DOI:10.1080/00102207308952362

出版商:Taylor & Francis Group    

年代:1973

数据来源: Taylor