APPLICATION OF AN ELECTRO-OPTICAL TWO-COLOR PYROMETER TO MEASUREMENT OF FLAME TEMPERATURE FOR LIQUID OXYGEN HYDROCARBON PROPELLANT COMBINATION

摘要

The development and application of an electro-optical two-color pyrometer for the measurement of temperature and emissivity in the exhaust gases from an open-tube combustor using liquid oxygen and a hydrocarbon fuel are described. Measurements were made during both normal and oscillatory combustion. Temperature variations up to 1000° R and emissivity variations of 10 to 1 were found to occur during combustor operation;the variations were sporadic and periodic during normal and oscillatory operation, respectively. Periodic variations at a frequency of 1000 cycles per second were predominant;however, smaller amplitude oscillations at higher frequencies were also present. Satisfactory correlation was obtained between temperatures measured simultaneously by the two-color method and by a microwave absorption technique. Agreement between temperature and sound intensity change was also found to exist. During many combustion experiments radiation intensity varied inversely with temperature and directly with emissivity, indicating a need for caution in the interpretation of combustion photographs on the basis of light intensity.