Temperature field measurements in a premixed turbulent cool flame

A turbulent premixed heptane-air cool flame is investigated in order to obtain information concerning the influence of combustion on turbulence. The cool flame is stabilized in a conico-cylindrical reactor where turbulence is generated by a perforated plate. A maximum temperature that does not exceed 550°C and the extended reaction zone of the turbulent cool flame allow the use of a hot-wire anemometer as a resistance thermometer to measure the turbulent temperature field in the flame. Temperature fluctuations in the flame, their spectra and dissipation microscales are determined. Similar measurements are also executed in a non reacting hot (≈400°C) turbulent air flow traversing the same reactor. Comparisons are then established between the characteristics of thermal turbulent fields, at comparable mean temperature, with and without chemical reactions due to combustion.