Simultaneous amplitude and phase contrast imaging of burning fuel particle and flame with digital inline holography: Model and verification

Three-dimensional (3D) quantitative measurements of reacting multiphase micro-objects are of great interest in fuel particle combustion, which is composed of an inner fuel particle and an outer gas flame. Three models of digital inline holography of this composite fuel particle in the framework of light scattering and diffraction theories have been proposed, and then verified with reported experimental observations. Results show that the dispersed fuel particle and the gas flame distinguish in the reconstructed amplitude and phase contrast images, and reveal that the low extinction efficiency and phase shifting of the highly transparent, weakly scattering gas flame accounts for the difference.