Recent advances in the measurement of strongly radiating, turbulent reacting flows

Recent advances in diagnostic methods are providing new capacity for detailed measurement of turbulent, reacting flows that are strongly radiating. Radiation becomes increasingly significant in flames containing soot and/or fine particles, and also increases with physical size. Therefore many flames of practical significance are strongly radiating. Under these conditions, the coupling between the turbulence, chemistry and radiative heat transfer processes is significant, making it necessary to obtain simultaneous measurement of controlling parameters. These environments are also particularly challenging for laser-based measurements, since soot and other particles increase the interferences to the signal and the attenuation of the beam. The paper reviews the influence of physical scale and of the properties of the medium on approaches to perform measurements in such strongly radiating flows. It then reviews the recent advances in techniques to measure temperature, mixture fraction, soot volume fraction, velocity, particle number density and the scattered, absorbed and transmitted components of radiation propagation through particle laden systems. Finally it also considers remaining challenges to diagnostic techniques under such conditions.