H2O温度二维分布的滤波反投影重建

利用可调谐半导体吸收光谱技术实现燃烧场温度二维分布重建。设计H2O模型温度分布范围为300~1300 K，高斯型分布，利用Radon变换模拟实验测量结果。采用滤波反投影算法重建了两条吸收谱线强度场，进而得到气体温度二维分布，重建结果与模型符合较好。研究了不同投影数目和随机噪声对重建结果的影响，结果表明:随着投影数目的减少和噪声幅值的增加，重建温度分布均方误差增大，图像重建效果变差。当投影数目减小到4个，重建温度场已不能完全反映原始温度场信息。

Two-dimensional water temperature reconstruction by filtered back-projection method

The reconstruction of water temperature in combustion is realized by the tunable diode laser absorption spectroscopy technique. The model for H2O temperature distribution is assumed as a Gaussian function, ranging from 300 K to 1300 K. Radon transform is used to simulate the experimental results. The reconstruction of temperature distribution is achieved by reconstruction of two temperature-dependent line strengths based on the filtered back-projection method. The temperature reconstruction result agrees well with the original model. Moreover, the influences of the number of projections and random errors in projections on reconstruction are also studied. The simulation results indicate that the decrease in projection number or the increase in noise increases the mean square error of the reconstructed temperature, deteriorating the reconstructed image. The temperature reconstruction can not reveal the original temperature distribution when the projection number reduces to four.