Image based temperature field reconstruction for combustion flame

We present a novel solution to accurately reconstruct three-dimensional temperature field for combustion flame. Traditional flame temperature field reconstruction methods ignore the effects of flame refraction. However, flame is a kind of inhomogeneous medium, traveling inside which the light rays will be bent. The neglect of refraction will lead to poor accuracy of the reconstructed results. In this paper, we propose a new model to establish the relationship between the flame radiation and the radiance field, which fully considers the refractive effect of the refraction index changing. We use high dynamic range (HDR) cameras to take flame images, calculate temperature from radiance with a lookup table between them, and put forward an algorithm to reconstruct the flame temperature field. The experimental results on real flame accord with the physical facts, which demonstrate the validation of our solution.