探讨用于气固多相流检测的广义动态重建算法

Exploratory Study of the Generalized Dynamic Rebuilding Algorithm for Testing and Measuring a Gas-solid Multi-phase Flow

通过监测气固两相流的流速和流量值,明晰输送流体的流动特性,确保气力输送过程顺利进行。电容层析成像技术作为气固多相流的检测技术之一,关键是图像重建环节。通过选取恰当的图像重建算法,反演被输送流体的截面分布特性。为了改善ECT系统的重建图像质量,提高检测技术的精确性,提出一种集合被测流体的空间约束、时间约束和流体的流动反演信息的广义动态图像重建算法。将数值试验与常规的图像重建算法分析比较发现,该算法的重建图像结构最清晰。实验呈现用该算法反演的气力输送粉煤灰过程。两者明显体现了该动态重建算法的优势。

Through monitoring the flow speed and rate of a gas-solid two phase flow,the flow characteristics of the fluid transmitted was clarified and the pneumatic transmission process was successfully performed.The capacitance topography technology is regarded as one of technologies for detecting a gas-solid two phase flow and the key lies in its image rebuilding link.Through choosing a proper image rebuilding algorithm,one can reversely deduct the distribution characteristics of the fluid transmitted in a section.To improve the rebuilding image quality of the ECT system and enhance the accuracy of the detection technology,presented was a generalized dynamic image rebuilding algorithm integrating the space restriction,time restriction and reverse deduction information of the fluid flow.By analyzing and comparing the numerical test and the conventional image rebuilding algorithm,the authors believe that the image structure rebuilt by using the algorithm in question should be clearest.The test showed the pulverized coal and ash pneumatic transmission process as reversely deducted by using the algorithm in question.Both coal and ash obviously embodied the advantage of the dynamic rebuilding algorithm.