Flame temperature reconstruction through a multi-plenoptic camera technique

Abstract

Due to the variety of burner structure and fuel mixing, flame temperature distribution is not only irregular but also complex. Therefore, it is necessary to develop an advanced temperature measurement technique, which can provide not only adequate flame radiative information but also reconstruct complex flame temperature accurately. In this paper, a novel multi-plenoptic camera imaging technique is proposed which provides adequate flame radiative information from two different directions and also reconstructs the complex flame temperature distribution accurately. An inverse algorithm, i.e. non-negative least squares, is used to reconstruct the flame temperature. The bimodal asymmetric temperature distribution is considered to verify the feasibility of the proposed system. Numerical simulations and experiments were carried out to evaluate the performance of the proposed technique. Simulation results demonstrate that the proposed system is able to provide higher reconstruction accuracy although the reconstruction accuracy decreases with the increase of noise levels. Meanwhile, compared to the single plenoptic and conventional multi-camera techniques, the proposed method has the advantages of a lower relative error and better reconstruction quality even with higher noise levels. The proposed technique is further verified by experimental studies. The experimental results also demonstrate that the proposed technique is effective and feasible for the reconstruction of flame temperature. Therefore, the proposed multi-plenoptic camera imaging technique is capable of reconstructing complex flame temperature fields more precisely.