Experimental Data on Suppression of Turbulent Combustion

When the flame propagates, the output signal grows. This growth is not the only indicator of flame expansion. 

The speciflc feature of the investigated process is the fact that upon heating the suspended micro-droplets are evaporated in the reaction zone and turn into the gas phase. The droplets evaporation leads to an increase in the modulated signal amplitude of the corresponding IR emitter. The measurement of modulated signal was an important complement to the flame indication system in the lean H2 + air mixtures where the natural radiation of combustion products is comparable to the limiting sensitivity of the photo-detector. 

The known micro-droplets volume concentration allows identification of the combustion mixture composition at the instant of ignition. Then, according to [20, 21], the saturated steam volume concentration was calculated from the 

Here - the water molecular weight, Pl - the water density in the liquid phase, 

R - the universal gas constant. At the instant of ignition the mixture pressure gas P = Pq = Q. MPa and the temperature did not exceed 373 K. The water density was changed insignificantly in the temperature range 273 K T 373 K 958.3 Pl 999.9 kg/m, and therefore, for the calculations Pl = 979 kg/m was used. The expression for P does not contain the combustion gas molecular weight that depends on the H2 content in the air mixture. 

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