Flame Temperature of Propellants Measurements

Combustion (Flame) Temperature of Propellants Measurements. Optical methods are the most widely used for the measurement of flame temperature. Since the study of a flame depends not only on temperature, but also on other factors (the radiation factor, the chemical reactions in the gases, etc), it is necessary first of all to study the spectral characteristics of the objects under investigation. Flame spectra were studied in Russia on the ISP-51 spectrograph 

In the pressure interval studied, (147-980) 10 newton m , the flame spectrum of NG powder and RDX was continuous except for several lines of the alkali metals. This permitted determination of temperature by optical methods 

When combustion proceeds under high pressure, separate atoms and molecules may no longer be regarded as isolated systems. Owing to their interaction, broad energy bands arise from the sharp energy levels of the atoms and molecules. The continuous spectra of flames 

The use of the infrared pyrometric method extended significantly the range of measurement. Infrared pyrometry has the advantage of being equally adaptable to luminous low-transparency and to nonluminous flames. 

With this apparatus (Ref 2) the temperature in the flame brush could be determined in the range 600-3500° K. A PbS photoresistor was used as the infrared radiation receiver it has significant sensitivity and low visual persistence 

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