During the temperature field measurement for boilers using acoustic tomography method

the accuracy and speed of the reconstruction algorithm plays an important role in reconstructing the temperature field. The principle of reconstructing temperature field based on pixel segmentation was analyzed and the three-dimensional variational algorithm(3 DVAR) was adopted in temperature field reconstruction. The solving of inverse problem of the temperature field reconstruction was come down to a minimum problem of a quadratic function characterizing the deviation between the analysis field and observation field as well as the analysis field and background field. The objective function was extended according to different weights. The objective function was solved by conjugate gradient method. Numerical simulation was realized in four temperature models respectively. The results show that

the precision and numerical stability of the 3 DVAR-based reconstruction method are higher than that of the least squares and algebra reconstruction technique.