CN202101706U - Electromagnetic flowmeter sensor with elliptical inner pipeline - Google Patents

Abstract

The utility model relates to a structural design of an electromagnetic flowmeter sensor in a narrow space. A measuring pipe is elliptical, electrodes of an electromagnetic flowmeter are positioned at two ends of a major semi axis of an elliptical inner pipeline, and an electromagnetic flowmeter excitation structure is positioned at two ends of a miner semi axis of the elliptical inner pipeline. An inner diameter pipeline of the electromagnetic flowmeter is designed as an elliptical structure so as to solve the problem, and the patent can design a magnet excitation coil space larger than the existing round structure for the electromagnetic flowmeter sensor with a narrow long pipe diameter space, thus ensuring the obtaining of excitation signals of the electromagnetic flowmeter to a certain extent, and more importantly, obviously enlarging the flow measurement range of the flowmeter compared with the traditional flowmeter with a round structure. The electromagnetic flowmeter sensor is applicable to measurement on flow in the narrow space.

Description

A kind of interior conduit is disciform electromagnet flow meter sensor

Technical field

The invention belongs to instrument and meter and make the field, relate in particular to the structural design of electromagnet flow meter sensor in a kind of long and narrow space.

Background technology

Electromagnetic flowmeter is broad with its measurement range, uses reliably, and is easy to maintenance, and advantages of simple structure and simple has wide application prospect in flow velocity, flow production in measuring.The measurement of electromagnetic flowmeter flow has the following advantages, and neither receives the influence of external factor such as temperature and pressure, does not also receive the influence of the characteristic of fluids such as fluid density and viscosity itself; Because its smooth interior, without hindrance fluid element so convection cell does not produce resistance, just can not produce the pressure loss yet.Therefore, electromagnetic flowmeter once was widely used in ground flow measurement single-phase, conductive fluid.But under the long and narrow environmental baseline of some measurement spaces, design has proposed challenge to electromagnet flow meter sensor.

In recent years, need the electromagnetic flowmeter under the long and narrow space to measure in some special dimensions, and need to guarantee certain flow measurement range.This just makes current comparatively ripe ground flow and fluid components surveying instrument be difficult to promote the use of these fields, and this just needs development to be fit to the flowrate measuring tool under the harsh space environment.

At present the electromagnet flow meter sensor interior conduit is traditional round basically, and just the internal measurement zone is round.If under long and narrow space, use electromagnetic flowmeter, round electromagnet flow meter sensor design can make the measured zone area reduce, and makes flow measurement range limited.Along with the needs of industrial development, the electromagnet flow meter sensor under the research and design long and narrow space is a crucial thing.

Summary of the invention

The objective of the invention is to propose a kind of method that in long and narrow space, designs the electromagnet flow meter sensor structure; This method is that the round interior conduit of traditional electromagnet flow meter sensor is designed to ellipse; Wherein electrode is positioned at the major semi-axis two ends of ellipse interior conduit, and the excitation structure design is at the two ends of ellipse pipeline minor semi-axis measuring tube.Interior conduit is that the shell (outer tube wall) of ellipse flowmeter sensor can be designed to ellipse cylinder or four prisms cylinder structure.The realization of this sensor construction makes the flow measurement range of the electromagnet flow meter sensor under long and narrow space increase, and can dependable flow instrumentation amount signal obtain.For the realization of under long and narrow space, measuring the electromagnetic flowmeter of big flow range provides possibility.

Of the present invention in long and narrow space the electromagnet flow meter sensor structure comprise coil, magnetic core, electrode and immobilising device thereof, lining, inner diameter wall, outside diameter wall; The measured zone of electromagnetic flowmeter (measuring tube space); Said measuring channel is an ellipse, and just interior conduit is an ellipse.The present invention changes into the ellipse pipeline with original electromagnetic flowmeter interior conduit, has reduced the requirement of electromagnet flow meter sensor width distance, under long and narrow space, is able to lay.

Electromagnet flow meter sensor ellipse pipeline configuration; Two electrodes are positioned at the transverse two ends; Under limited space, make electrode distance become big, in the time of can knowing that according to formula (1) electromagnet flow meter sensor becomes the ellipse pipeline, the flowmeter induced signal is influenced by electrode distance.Constant when measured zone magnetic field, through fluid velocity one regularly, electrode is positioned at oval pipeline major axis two ends, and electrode distance D increases can increase the flowmeter induced signal, helps obtaining of electromagnetic flowmeter signal.

$E=\frac{\mathrm{d\Φ}}{\mathrm{dt}}=B\frac{\mathrm{dA}}{\mathrm{dt}}=\mathrm{BD}\frac{\mathrm{dl}}{\mathrm{dt}}=\mathrm{BD}\stackrel{\‾}{V}---\left(1\right)$

Formula (1) is the induced signal result of guestimate cutting magnetic line gained, and in the formula, D is the length of cutting magnetic line, just the distance of electrode; B is a magnetic field intensity;

is fluid average velocity.

The design of ellipse interior conduit makes flowmeter survey zone sectional area increase to some extent at the electrode two ends under long and narrow space, so the ellipse electromagnetic flowmeter has increased the flow measurement range of electromagnetic flowmeter under long and narrow space.

Be set in that the round electromagnetic flowmeter internal diameter of traditional type pipeline radius design maximum is a under a certain long and narrow space, pipeline section is long-pending for being about 3.14a ²If electromagnetic flowmeter is designed to the ellipse pipeline, the interior conduit minor axis is designed to a, major axis is b, if b=k*a, then pipeline section is long-pending is k*3.14a ²Can know under long and narrow space ellipse flowmeter be traditional round flowmeter survey scope k doubly, can carry out the design of size sensor according to on-the-spot structure and flow measurement specific requirement.

Because excitation structure is positioned at ellipse pipeline minor semi-axis measuring tube two ends, the length of adjustment minor semi-axis that can be suitable increases the space of field coil, and then under limited space, for excitation structure better accommodation space is provided.

According to Biot-Savart law, estimate the magnetic induction density of field coil on the axis center of circle.When inside and outside the flowmeter sensor during pipeline ellipse, set B ₁With B ₂Be respectively the round magnetic induction density that produces with the ellipse electromagnetic flowmeter of tradition.Through its coil centre point magnetic induction density of Biot-Savart law estimation, shown in (2), B is a magnetic induction density in the formula; I is the size of current through solenoid coil; R is the circular coil radius; N is a coil turn; X is the distance of circular coil axis apart from the center of circle, and small tenon 1 and 2 is represented the round value corresponding with the ellipse electromagnetic flowmeter of tradition respectively.Here for estimation, above-mentioned x is made as 0, I is made as identical.

$C=\frac{B_1}{{\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="DEST\_PATH\_HSB00000637360100011.png,DEST\_PATH\_HSB00000637360100021.png"\; state="\{\{state\}\}">B</figure-callout>}}_2}=\frac{I_1{N}_1{R}_1{(R_2^2+x^2)}^{\left(\frac{3}{2}\right)}}{I_2{N}_2{(R_1^2+x^2)}^{\left(\frac{3}{2}\right)}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="DEST\_PATH\_HSB00000637360100011.png,DEST\_PATH\_HSB00000637360100021.png"\; state="\{\{state\}\}">R</figure-callout>}}_2}=\frac{N_1{I}_1{R}_2}{N_2{I}_2{R}_1}=\frac{N_1{R}_2}{N_2{R}_1}---\left(2\right)$

Pipeline was ellipse and traditional round electromagnetic flowmeter comparison diagram inside and outside Fig. 3 was shown as under the long and narrow zone.By knowing among the figure, disciform electromagnetic flowmeter excitation space is big, that is to say that the turn number N that can lay is more; On the other hand, disciform electromagnetic flowmeter produces magnetic induction density uniformly in measured zone, and field coil R is bigger than traditional round electromagnetic flowmeter; And comparison diagram 3 can be known; When ellipse electromagnetic flowmeter interior conduit major semi-axis increases; Need field coil R constantly to increase; It is limited that but disciform electromagnetic flowmeter excitation space (that is to say turn number N) increases, so two parameters of suitable within the specific limits adjustment can be so that the magnetic induction density that electromagnetic flowmeter produces be close.

In order better to increase the size of ellipse electromagnetic flowmeter interior conduit major semi-axis, and do not influence excitation intensity, can adopt interior conduit to be the flowmeter sensor that ellipse, shell (outer tube wall) are designed to the four prisms cylinder structure, as shown in Figure 2.Fig. 4 has shown to be that long and narrow regional lower sensor interior conduit is four prism type and traditional round sensor comparison diagram for the ellipse Outer Tube.By finding among Fig. 4; When magnetic core and field coil width H be no more than ellipse flowmeter inner diameter wall and outside diameter wall apart from the time; And during long and narrow space (y direction of principal axis) long enough; Field coil cross-sectional length K just can constantly increase, and then field coil number of turn N will increase, thereby balance increases the influence that the measured zone magnetic induction density that brings reduces because of ellipse flowmeter interior conduit major semi-axis increases field coil R.

Under long and narrow space, the present invention compares with existing traditional round electromagnetic flowmeter: reequiped the design proportion on flowmeter sensor electrode direction and the excitation direction on the one hand, made the use of electromagnetic flowmeter under its suitable long and narrow space; Through increase, increased the flow measurement range of electromagnetic flowmeter to a great extent on the other hand to the measured zone sectional area; And can dependable flow meter signal obtain.In actual the use, can confirm ellipse interior conduit electromagnet flow meter sensor size design parameter according to concrete engineering duty construction and flow range measurement requirement.Through accompanying drawing the present invention is further specified below.

Description of drawings

Fig. 1 is an ellipse electromagnet flow meter sensor embodiment for the inside and outside pipeline of the present invention;

Fig. 2 is that ellipse, Outer Tube are quadrangular type electromagnet flow meter sensor embodiment for interior conduit of the present invention;

Fig. 3 is under the long and narrow zone, and inside and outside pipeline is ellipse and traditional round electromagnetic flowmeter comparison diagram.

Fig. 4 is under the long and narrow zone, and the electromagnet flow meter sensor interior conduit is prismatic and traditional round sensor comparison diagram for the ellipse Outer Tube.

Embodiment

Describe the present invention below in conjunction with figure.Interior conduit is the oval structure electromagnetic flowmeter.Fig. 1 and 2 has shown that respectively the electromagnetic flowmeter interior conduit is disciform electromagnet flow meter sensor structure embodiment, shown in figure, icon keep the score not Biao Shi: 1 coil; 2 magnetic cores; 3 electrodes and immobilising device thereof; 4 linings; 5 inner tubal walls; 6 outer tube walls; 7 measuring channels (measured zone); 8 long and narrow installation regions; L is the width in long and narrow zone.The measuring channel of electromagnet flow meter sensor is an ellipse, and wherein electrode is positioned at ellipse pipeline major radius two ends, between ellipse pipeline short radius two ends place's inner diameter wall and outside diameter wall, is magnetic core, and the magnetic core both sides are designed to solenoid coil.Shown in figure, because the flowmeter interior conduit is an oval structure, on flowmeter sensor ellipse minor semi-axis direction, can save accommodation space, this flowmeter sensor structure is fit to be applied to big flow measurement in the long and narrow space.

At embodiment one (among Fig. 1), the inside and outside caliber cross section of electromagnet flow meter sensor is ellipse, and promptly flowmeter sensor shell (outer tube wall) is the ellipse cylinder.Wherein ellipse flowmeter minor semi-axis can be placed in (x direction among the figure) on the direction narrower in the space, and the major semi-axis structure just in time is placed on the long and narrow direction (y direction among the figure), makes the arrangement of flowmeter effectively utilize long and narrow space.

At embodiment two (among Fig. 2), electromagnet flow meter sensor outer tube diameter cross section is a rectangle, and promptly flowmeter sensor shell (outer tube wall) is a four prisms cylinder.Wherein short limit, flowmeter shell (outer tube wall) square-section is placed in (x direction among the figure) on the direction narrower in the space; Long limit, square-section is placed on the long and narrow direction (y direction among the figure), and then makes the arrangement of flowmeter effectively utilize long and narrow space.Flowmeter sensor under this structure, the thickness H (as shown in Figure 2) of field coil and magnetic core should be not more than the distance of electromagnet flow meter sensor measuring tube to outside diameter wall, otherwise the coiling of electromagnetic flowmeter coil will encounter difficulties with installation.

Claims (3)

1. an interior conduit is disciform electromagnet flow meter sensor, it is characterized in that, measured zone is an ellipse, that is to say that measuring tube is an ellipse.

2. be disciform electromagnet flow meter sensor according to the described a kind of interior conduit of claim 1, it is characterized in that electrode of electromagnetic flowmeter is positioned at the major semi-axis two ends of ellipse interior conduit.

3. be disciform electromagnet flow meter sensor according to the described a kind of interior conduit of claim 1, it is characterized in that the electromagnetic flowmeter excitation structure is positioned at ellipse interior conduit minor semi-axis tube wall two ends.

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