基于多相流输运机理的过程层析成像方法

Conventional process tomography can only image one phase in the multiphase medium, and the imaging process can often be hindered by complex structures in a measuring domain. In this project we propose a new type of tomographic method that uses the mechanisms of multiphase flow to carry the information of the phase distribution in a complex domain, which enables the sensitivity map being formed that then combined with an image on a “probing sub-domain” to reconstruct the multiphase image on the higher dimension zone. The aim of this project is to find a new mechanism and form a multiphase tomography, and to form a practical technique to diagnose the leaks in the power plant reactor. The novelties and the merits of the method include：（1）the imaging process is related to the mechanisms of the fluid flow, which can produce a sensitivity map to reflect the effect of several phases, and perform spontaneous image reconstruction for several phases. (2) the image coupling between the sub-domain and higher dimension zone, which allows the image reconstruction for the later to be based on the image from a more easily scanned sub-domain, aided by the rules of fluid mechanics. (3) Indirect tracing: as the numerical solution of multiphase can reveal the inter relations between all the phases, if the distribution of one phase is known, the distributions of the other phases are naturally known. Therefore, some easily detectable phase can be a “tracer” for other phases and hence obtain their images. The study will be carried out by theoretical analysis, CFD simulation, and experiments. The new method will be expected to have a broad area of application and to become power tool for the diagnosis of the power industries reactors.

过程层析成像通常只对多相物质中一个组分成像，并易受测量空间中复杂构件的干扰，难以成像。本课题提出一类新型层析成像方法，利用多相流机理传递出复杂空间的分布信息，建立多相敏感场，再根据某“探测子域”的图像，重建高维空间的多相分布图像。研究目标为：发现新机理，建立“多相层析成像”方法；造就一种实际方法，诊断核电反应堆的燃料棒泄露。研究的创新点和优势包括：（1）被测物质分布的层析成像，与多相流机理联系，可形成多相物质作用的敏感场，以及多项物质的同时成像；（2）子域-高维空间耦合的成像方法：利用一个易于探测的子域图像，结合多相流规律，重建高维空间的完整图像；（3）间接示踪方法：根据多相流数值解可以同时确定多相分布的特点，选择某种利于测量的相进行成像，即可据此获取多个其它相的分布。研究将以理论分析，CFD仿真，实验等方式进行。这种新方法将有广阔的应用领域，并有望成为核电反应堆检测的有力工具。

本课题研究了一类新型层析成像方法，利用多相流机理传递出复杂空间的分布信息，建立多相敏感场，再根据某“探测子域”的图像，重建高维空间的多相分布图像。研究的创新点和优势包括：（1）被测物质分布的层析成像，与多相流机理联系，可形成多相物质作用的敏感场，以及多项物质的同时成像；（2）子域-高维空间耦合的成像方法：利用一个易于探测的子域图像，结合多相流规律，重建高维空间的完整图像；（3）间接示踪方法：根据多相流数值解可以同时确定多相分布的特点，选择某种利于测量的相进行成像，即可据此获取多个其它相的分布。这种新方法将有广阔的应用领域。.研究分理论仿真研究和实验研究两大部分。理论仿真研究部分提出了新型成像机理，新新机理通过仿真得到了初步的肯定。在进一步的实验研究部分验证了项目中提出的成像新机理，以及新型数据采集和分析方法。取得了预期的结果。