Inner and outer tube type flowmeter and flow detection method

Abstract

The invention provides an inner and outer tube type flowmeter and a flow detection method. The inner and outer tube type flowmeter is characterized in that an inner tube as long as an outer tube is arranged in the outer tube, and the inner tube comprises an inlet tube, a shrinking tube, a pressure tapping tube, an expanding tube and an outlet tube that are connected in sequence. Compared with the traditional inner and outer tube differential flowmeters, the inner and outer tube type flowmeter is provided with the inlet tube and the shrinking tube at the front end of the pressure tapping tube, a fluid entering the inner tube experiences shrinking, accelerating, expanding and decelerating, and a fluid entering a gap between the inner and outer tubes experiences expanding, decelerating, shrinking and accelerating. A difference between inner and outer tube fluid speeds is maximum, to be specific, pressure tapping is performed at the middle tube with maximum pressure difference, and a maximum differential value can be acquired. The inner and outer tube type flowmeter is simple in structure and reasonable in design, the differential pressure value of the fluids in the inner tube and outer tube is increased, the sensitivity, accuracy and energy efficiency of the inner and outer tube type flowmeter are enhanced, and final measurement results are accurate and reliable.

Description

technical field [0001] The invention relates to the technical field of two-phase flow detection, in particular to an inner and outer tube type flowmeter and a flow detection method. Background technique [0002] Differential pressure flowmeter is one of the most widely used flowmeters in the measurement of two-phase flow, and it is currently recognized as a flowmeter that can work stably under all flow patterns of two-phase flow. [0003] Differential pressure flowmeters are based on a split-phase or homogeneous model, which establishes the relationship between flow and pressure drop. Among them, the longest research history is the throttling differential pressure flowmeter, and the differential pressure method is basically found in the throttling differential pressure flowmeter. The flowmeter has the advantages of easy installation and reliable operation, and has formed a mature international standard in the course of many years of research. At present, many manufacturers ...

AI Technical Summary

Problems solved by technology

However, there are still some shortcomings that are difficult to overcome. For example, the tail of the V-cone flowmeter is a blunt body structure, and the fluid flow is separated, forming a large number of vortices and causing a large pressure loss; compared with the electromagnetic flowmeter, its range ratio is relatively narrow; The L-shaped cantilever structure may generate vibration when the flow is large

[0007] For the above-mentioned orifice plate, Venturi tube and V-cone flowmeter, the throttling method is realized by changing the total flow area of ​​the fluid, which will inevitably cause disturbance to the fluid itself, and the differential pressure signal will be unstable.

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