INVESTIGATION OF THE FEASIBILITY OF MEASURING THE CHAMBER TEMPERATURE OF SOLID PROPELLANT ROCKET MOTORS BY USING MICROWAVE ATTENUATION MEASUREMENTS

Abstract

The analysis of a plane wave propagating through a homogeneous plasma region of dimensions large compared to the signal wavelength has shown that the wave attenuation can be related to physical parameters of the plasma such as electron density, temperature, and pressure. In this report, the plasma in the combustion chamber of a small solid propellant rocket motor is used to investigate the feasibility of determining the temperature of the plasma by using microwave attenuation data. Potassium perchlorate is substituted for some of the ammonium perchlorate in the propellant to give an electron density that produces an easily measurable attenuation. The theoretical results show that for a known propellant composition and potassium perchlorate concentration, both the plasma temperature and chamber pressure at equilibrium may be found from one attenuation measurement. Also, for a known thermodynamic state of the plasma, the electron density may be found from the attenuation data. The method of microwave analysis is shown to be very useful in the study of transient phenomena in that no transducers are required; hence, the time response of the measurement is limited only by the microwave detection circuitry. This technique may be used to study localized disturbances within the plasma region.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1970
Accession Number
AD0712703

Entities

People

  • R. G. Olsen
  • Richard W. Grow

Organizations

  • University of Utah

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Ammonium Perchlorate
  • Chemical Reactions
  • Combustion
  • Combustion Chambers
  • Combustion Products
  • Computer Programs
  • Computers
  • Electric Fields
  • Electron Density
  • Free Electrons
  • Frequency
  • Ignition
  • Ionization
  • Rocket Engines
  • Solid Propellants
  • United States

Fields of Study

  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Plasma Physics / Magnetohydrodynamics
  • Rocket Propulsion.

Technology Areas

  • Microelectronics
  • Microelectronics - Microelectromechanical Systems