Analysis on Flame Kernels of a high-speed diffusion jet flame via 3D tomographic measurements

This work reports an experimental study on the flame kernels in a high-speed C2H4/air diffusion jet flame using three-dimensional (3D) tomographic measurements at 15 kHz. For this purpose, the chemiluminescence signals of both the flame kernel and stable flame were simultaneously captured by nine fiber-based-endoscopes and a high speed camera operated at 15 kHz. The tomography reconstructions based on the parallel beam imaging and the algebraic reconstruction technique (ART) algorithm were performed for each frame to reconstruct the temporal resolved, 3D distributions of the flame kernel and stable flame. Based on the reconstructions, the 3D volume, chemiluminescence intensity and the velocity trajectory of the flame kernels were extracted to study the mechanism of the formation, propagation and extinction process of the flame kernel in the high-speed diffusion jet flame.