Caractérisation de la fraction volumique et de la température des suies d'une flamme de diffusion établie en micropesanteur

Abstract

The soot has a dominant radiative role in microgravity diffusion flames. In fact, the radiative losses are particularly important in the trailing edge of the flame, where the combustion products, especially the soot, concentrate due to lack of convection. A new optical technique in microgravity is proposed that combines modulated absorption and emission measurements at two wavelengths simultaneously: 470 nm and 530 nm. A bicolor matrix of LEDs (blue and green) allows the emission of a series of little beams that cross the flame and form a detailed cartography of extinction along the flame. In this way, the conditions in the trailing edge of the diffusion flame, where quenching occurs, can be characterized in soot volume fraction and temperature.