Tomographic Imaging Using Multi-Simultaneous Measurements (TIMes) For Single-Shot Emission Reconstructions In Turbulent Spray Flames
F. J. W. A. Martins (1), C. T. Foo (1), A. Unterberger (1), K. Mohri (1,2,3)
(1) Institute for Combustion and Gas Dynamics – Tomography Group, University of Duisburg-Essen, Germany
(2) Institute for Combustion and Gas Dynamics – Fluid Dynamics, University of Duisburg-Essen, Germany
(3) Center for Nanointegration Duisburg-Essen (CENIDE), Germany
Tomographic imaging using multi-simultaneous measurements of emissions is applied to three operating conditions of the SpraySyn burner in order to investigate the turbulent flame morphology and its potential impact on the flame spray pyrolysis. Instantaneous and time-averaged three-dimensional fields of CH* chemiluminescence (flame front marker) and atomic Na emission from NaCl dissolved in the injected liquid solution (linked to hot products of the spray flame) are reconstructed using 29 cameras divided between them. The association between CH* and Na signals is analyzed using isosurface visualizations, combined slices, profiles and scattered plots. The instantaneous results unveil the complex reacting turbulent flow and regions of interplay between the flame front and the hot spray products. The time-averaged results show that the investigated spray flames are slightly asymmetric near the burner exit and evolve towards symmetric bell-shaped distributions further downstream. In the context of flame spray pyrolysis, the flame asymmetries potentially lead to inhomogeneous characteristics of the final synthesized material.
