针对燃烧室回流区三维辐射空间在CCD(Charge coupled device)靶面的辐射图像分析局限于二维温度场计算,以及在三维温度场重构过程中摄像机安装台数受限问题,提出了二维矩形线性插值虚拟CCD探测器安装算法,解决了现场安装CCD探测器个数的受限和滤波后投影算法因投影数少导致的三维重构误差问题。通过对已知的CCD探测器和虚拟CCD探测器采集二维图像获取的投影数据进行滤波反投影得到燃烧室回流区深度方向辐射强度场分布,在此基础上,采用实验校正的双波长比色测温公式得到温度场分布,实现了燃烧室回旋区深度温度场分布的在线监控。实验室小型煤气实验表明,该算法是可行的,达到了燃烧室回流区工况在线监测的要求,为进一步研究燃烧室燃烧效率和稳定性奠定了基础。
Aiming at the questions of raceway section two-dimension temperature distribution from two-dimensional image accumulated by three-dimensional radiation space and three-dimensional temperature reconstruction error caused by limited charge coupled device (CCD) sensors for a sudden spread combustion chamber, the two-dimension rectangle interpolation virtual CCD sensor installation algorithm is provided as a new technology for solving the difficulties of installing more CCD sensors and filtered back projection reconstruction error caused by limited projection numbers. The radiation intensity projection data got from flame image collected from the installed CCD sensors and computed virtual CCD sensors is interpolated for filtered back projection to computer intensity distribution and calibrated bi-color method is used to calculation temperature in raceway depth direction. The results of experiments on a mini-type coal gas furnace and practice test showed that the algorithm is accurate and credible and realized the on-line monitoring for sudden spread combustion chamber raceway depth direction. At the same time, the useful information is provided for further studying combustion working state for the sudden spread combustion chamber.