Measuring apparatus for multiphase fluid imaging based on bimodal silk screen and measuring method thereof

Abstract

The invention belongs to the technical field of multiphase fluid imaging and relates to a bimodal (conductance and capacitance) sensing imaging device based on a silk screen. A sensor consists of a plurality of parallel leads with insulated or noninsulated outer surfaces in the longitudinal direction, and the leads with insulated or noninsulated outer surfaces are distributed alternatively; the sensor consists of a plurality of parallel leads in the transverse direction, and each lead is formed by connecting small sections with insulated or noninsulated outer surfaces in series. The transverse leads are connected to an excitation signal generator, and the longitudinal leads are connected to a measuring circuit. By measuring conductance and capacitance of the leads that are mutually perpendicular to each other, the invention determines the distribution information of each phase of the multiphase fluid on the whole pipe section and obtains the spatial distribution of conductivity and dielectric coefficient of the fluid or the powder in a same tangent plane simultaneously without using a complex reconstruction algorithm.

Description

Technical field [0001] The invention belongs to the technical field of imaging of multiphase fluids, and relates to a dual-mode imaging system based on a silk screen. Background technique [0002] The phenomenon of multiphase flow is widely present in modern engineering fields such as petroleum, chemical industry, energy and power. The online display and identification of multiphase flow patterns are of great significance to the monitoring and fault diagnosis of the production process. At the same time, in some fields of fluid measurement, the ability to accurately image the flow cross-section of multiphase fluid in real time is an urgently needed technology for many applications in the industry. [0003] Process tomography technology takes multiphase flow as the main research object, and can obtain the two-dimensional / three-dimensional temporal and spatial local micro-distribution information of multiphase fluid. This is a multiphase flow with complicated and changeable flow char...

AI Technical Summary

Problems solved by technology

For example, the ERT / ECT dual-mode imaging system compound array sensor whose publication number is CN1793879, but its resistive mode and capacitive mode synchronous excitation will produce coupling phenomenon, which increases the complexity of the hardware system; time-sharing excitation corresponds to time-sharing measurement, Simultaneous measurement of the same flow profile cannot be achieved

And it inherits the common shortcomings of ECT and ERT, that is, the imaging technology has strong nonlinear, pathological and soft field characteristics, which makes the image reconstruction process complicated

In order to improve the resolution of the image, a complex iterative algorithm must be used, which makes the real-time performance very poor; if a simple back-projection algorithm is used to improve the real-time performance, then the spatial resolution of the image is very low

Spatial resolution and real-time performance have become an irreconcilable contradiction

These characteristics limit the practical application of electrical tomography (including dual-mode) technology

[0005] The two-phase fluid mesh capacitive imaging method with the application number 200610074260.9 uses an interventional method to measure the two-phase flow, which has high resolution and real-time performance, but it is only based on the principle of capacitance and cannot be used for fluids with different conductivity. Measurement

In many chemical and multiphase flow processes, multiphase fluids (such as oil / gas / water mixtures in oil fields) are composed of conductive and dielectric substances, and the technology described in the application number 200610074260.9 will fail

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