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Thermophysical Properties of Propellants

  • R. L. Shoemaker
  • J. A. Stark
  • L. G. Koshigoe
  • R. E. Taylor

Abstract

The determination of the thermophysical properties of some solid propellants have been made. The two thermal properties measured were specific heat and thermal diffusivity. The specific heat was measured by using a differential scanning calorimeter (DSC) and thermal diffusivity was measured by the flash diffusivity method. The samples used included both single crystal and pressed powders of ammonium perchlorate (AP), HMX and RDX.

The measurements of the propellants’ specific heat required the modification of both the DSC equipment and the technique to accommodate the decomposition products from the samples. A flow-through cover was installed for this purpose. The computerized control and analysis for the DSC was also changed. The specific heat of AP, HMX and RDX was measured using both small single crystals and small amounts of powder. The specific heat of the HMX in both its normal phase (beta) and the delta phase were obtained. There proved to be little difference in the specific heat between these two phases of the HMX.

The thermal diffusivity of HMX in pressed powder form was determined. It was necessary to develop a method of holding powdered samples so that propellants would not see the laser pulse directly in order to avoid excessive temperature rises or radiant energy transmission. A cup was designed to allow the powder to be pressed into it and to not allow an alternate heat path when the sample was under test.

Keywords

Thermal Diffusivity Differential Scanning Calorimeter Ammonium Perchlorate Beta Phase Specific Heat Measurement 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. [1]
    Boggs, T.L., Price, C.F., Zurn, D.E., Derr, R.L. and Dibble, E.J., “The Self-Deflagration of Cyclotetramethy-lenetranitramine (HMX),” AIAA/SAE 13th Propulsion Conference, Orlando, Florida, July 11–13, 1977.Google Scholar
  2. [2]
    Westrum, E.F. and Justice, B.H., “Molecular Freedom of the Ammonium Ion. Heat Capacity and Thermodynamic Properties of Ammonium Perchlorate from 5–300K,” J. Chem. Phys., Vol 50, No. 12, June 1969.Google Scholar
  3. [3]
    JANNAF Thermochemical Tables, Second Edition, NSRDS-NBS 37 D.R. Stull and H. Prophet, June 1971.Google Scholar
  4. [4]
    Velicky, R., Lenchitz, C. and Beach, W., “Enthalpy Change Heat of Fusion and Specific Heat of Basic Explosives,” Picatinny Arsenal, Dover, N.J., Technical Report 2504, Jan. 1959.Google Scholar
  5. [5]
    Wilcox, J.D., “Differential Scanning Calorimeter Methods in the Determination of Thermal Properties of Explosives,” Air Force Institute of Technology, Air University, Wright-Patterson Air Force Base, OH, Masters of Science Thesis, GAW/ME/67B-3, June 1976.Google Scholar
  6. [6]
    Baytos, J.F., “Specific Heat and Thermal Conductivity of Explosives, Mixtures and Plastic-bonded Explosives Determined Experimentally,” LA-8034-MS, Los Alamos Scientific Laboratory, Los Alamos, N.M.Google Scholar
  7. [7]
    Brill, T.B. and Karpowicz, R.J., “Solid Phase Transition Kinetics: The Role of Intermolecular Forces in the Condensed Phase Decomposition of Octahydro-1,3,5,7-Tetranitro-1,3,5,7-Tetrazocine (HMX),” J. Phys. Chem., Vol 86, 1982, pp 4260–4265.CrossRefGoogle Scholar

Copyright information

© Purdue Research Foundation 1985

Authors and Affiliations

  • R. L. Shoemaker
    • 1
  • J. A. Stark
    • 1
  • L. G. Koshigoe
    • 1
  • R. E. Taylor
    • 1
  1. 1.Thermophysical Properties Research LaboratoryPerdue University, School of Mechanical EngineeringWest LafayetteUSA

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