Library Subscription: Guest
Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections
International Journal of Energetic Materials and Chemical Propulsion
ESCI SJR: 0.149 SNIP: 0.16 CiteScore™: 0.29

ISSN Print: 2150-766X
ISSN Online: 2150-7678

International Journal of Energetic Materials and Chemical Propulsion

DOI: 10.1615/IntJEnergeticMaterialsChemProp.v5.i1-6.1040
pages 1018-1027

THERMAL PROTECTION WALL-EFFECT ON THE COMBUSTION OF A SOLID PROPELLANT AT SUBATMOSPHERIC PRESSURE

Claudio Zanotti
TEMPE - National Research Council Via Cozzi 53, 20125 Milano, Italy
Piero Giuliani
TEMPE - National Research Council Via Cozzi 53, 20125 Milano, Italy
Masahiro Kohno
Institute of Space and Astronautical Science, 3-1-1 Yoshinodai Sagamihara, Kanagawa 229, Japan

ABSTRACT

The solid rocket motors for high altitude applications operate under external vacuum conditions and for that reason, during their life, the inner motor pressure can reach values, which are lower than the measured Pressure Deflagration Limit (PDL) in laboratory tests. Although this condition should not allow any combustion process inside the motor, a small residual thrust is still active due to unexpected gases production. The motor's operating time becomes longer than the estimated one, and therefore this occurrence cannot be neglected in the motor design. The thermal insulator degradation, coupled to the propellant combustion or high temperature decomposition at pressures below the PDL, can be the main causes of this unpredicted motor performance. For those reasons, an experimental study to analyze the wall-effect due to the thermal protection presence, in contact with the burning propellant, has been carried out in order to find out which parameters are more sensible to this operating configuration. Results have demonstrated that the average propellant temperature increases when the burning surface approaches the thermal insulator because of the large value of the thermal wave thickness, especially when metallized propellents are used. Moreover, the radiant energy scattered by the inner part of the nozzle, or by the exposed thermal protection, is another possible cause that yields the propellant to bum, or gasify, below PDL. To verify this possibility, the degradation behavior of the thermal protections has been analyzed and results indicate that the energy amount emitted by these hot materials is enough to sustain the propellant combustion process below PDL.


Articles with similar content:

DEVELOPMENT OF HAN-BASED LIQUID PROPELLANT THRUSTER
International Journal of Energetic Materials and Chemical Propulsion, Vol.7, 2008, issue 2
Hiroyuki Mishima, Shujiro Sawai, Toshiyuki Katsumi, Keiichi Hori, Tetsuya Matsuo, Kenji Hisatsune
EXPERIMENTS AND OBSERVATIONS OF INTERACTION OF WATER MIST WITH POOL FIRES
Proceedings of Symposium on Energy Engineering in the 21st Century (SEE2000) Volume I-IV, Vol.0, 2000, issue
Weicheng Fan , Xishi Wang, Guangxuan Liao , Bin Yao , Xiaoping Wu
NEW HTPB/AP/Al PROPELLANT COMBUSTION PROCESS IN THE PRESENCE OF ALUMINUM NANO-PARTICLES
International Journal of Energetic Materials and Chemical Propulsion, Vol.7, 2008, issue 2
Yves Fabignon, Olivier Orlandi, Dominique Lambert, Jean Hommel, Jean-Francois Trubert
SURFACE HEAT RELEASE OF HTPB-BASED FUELS IN OXYGEN RICH ENVIRONMENTS
International Journal of Energetic Materials and Chemical Propulsion, Vol.5, 2002, issue 1-6
H. Stephen Jones, Grant A. Risha, George C. Harting, Joseph P. Arves, Arie Peretz, Donald E. Koch
MELT CAST EXPLOSIVE FRIABILITY STUDIES
International Journal of Energetic Materials and Chemical Propulsion, Vol.11, 2012, issue 6
Alice I. Atwood, Kevin P. Ford, C. J. Wheeler, Q. T. BuiDang, M. T. Gennrich, A. L. Daniels, E. Woods