Three-Dimensional Radiation Field Reconstruction of Engine Tail Flame Based on Optical Computed Tomography

Flame optical tomography is an indispensable part of rocket engine tail flame diagnostic technology. This paper proposes a method for reconstructing the three-dimensional radiation field of flame by optical tomography. When using the optical tomography to measure the three-dimensional radiation field of the flame, we need to use multiple array detectors, and at the same time, we must get the projection data of the three dimensional radiation field along the same direction. In order to obtain a high resolution flame three-dimensional radiation field, we did the following work. First, we perform high-precision calibration on telecentric camera sets. Then, we ensure alignment of the two-dimensional images in multiple directions by polar line correction. Finally, we reconstruct the 3D radiation field of each layer using the 2D flame image slices. We superimpose the radiation field of each layer to reconstruct the complete high precision flame three-dimensional radiation field. We conducted experiments on flame optical chromatography. We used six cameras to shoot the experiment platform from different directions. The reprojection error of the telecentric camera group calibration result is significantly better than the total station. Finally, we obtained a high-precision flame three-dimensional radiation field. We analyzed the experimental results and summarized them at the end of the paper.