The measurement of 3-D temperature distribution in flame by optical sectioning tomography

In this paper the technique of Optical Sectioning Tomography has been developed to measure 3-D temperature distribution in flame. The fundamental of this technique is based on the matter that a 3-D flame image can be regarded as a stack of sectioning images of the flame. By moving the camera along a line and hence shifting focused section, we can capture 2-D images for different sections with a stationary camera system. Then an image reconstruction algorithm that was previously proposed by the authors has been employed to reconstruct 3-D flame image from a set of 2-D sectional images. Since temperature distribution is directly related to the gray scales of the flame image, we can conveniently derive 3-D temperature distribution of the flame of interest. Preliminary experiments in the laboratory have been carried out with candle flame. It has been shown that this technique provides a potential approach for measuring 3-D temperature distribution.