SU1296945A1 - Device for measuring velocity of electroconductive liquid flow - Google Patents

Abstract

The invention relates to a measurement technique and allows extending the range of measurements of the direction of the velocity vector of a flow of an electrically conductive fluid and increase sensitivity. The transducer placed in the test medium is affected by the flow of electrically conductive fluid (EF). In an ECM moving in a magnetic field created in the gaps of the magnetic system of the converter, EMF is induced, proportional to the flow velocity and the intensity of the magnetic field. The outputs of the electronic unit will simultaneously have three voltages, the values of which are proportional to the values of the projections of the flux velocity vector on the coordinate axes of the measuring transducer, which determine the direction and magnitude of the flow velocity vector, the direction of which is arbitrary in the coordinate system of the measuring transducer. 7 il. about 16 (L to with 05 with SP

Description

The invention relates to a measuring technique, namely, electromagnetic devices for measuring the flow rate of an electrically conductive fluid, and can be used to measure the module and direct the velocity vector of a flow of an electrically conductive fluid in wide ranges of amplitude and frequency variations during oceanologic surveys.

The purpose of the invention is to expand the range of measurements of the direction of the velocity vector of the flow of an electrically conductive fluid and increase the sensitivity. .

Figure 1 shows a block diagram of a device for measuring the flow rate of an electrically conductive liquid and a circuit for connecting measuring electrodes to subtracting amplifiers; figure 2 - primary measuring transducer with one remote pole tip; in fig. 3,4, 5 — magnetic field strength vectors and components of the flow velocity vectors in the gaps of the magnetic system (at the points where the measuring electrodes are located) on three projections of the primary measuring transducer in the orthogonal coordinate system; Fig. 6 illustrates one of the possible mounting options for the primary transducer in a frame; Fig. 7 illustrates the electrical circuit for connecting the two-section excitation coils of the magnetic system of the first measuring transducer to the power supply unit.

The device for measuring the flow rate contains (Fig. 1) a primary transducer with measuring electrodes, twelve subtractive amplifiers 13-24, six addition blocks 25-30 and three subtractors 31-33.

The primary transducer has a magnetic system (FIG. 2), made of four magnetic conduits 34, which intersect in its middle part, with four two-section coils 35 and eight pole tips 36 Each pole tip 36 is made of magnetic material in the form of equilateral spherical triangles , with the conjugation of which a sphere is formed.

The two-section coils 35 are connected to the power supply unit (Fig. 7) as follows.

that the polarities of the pole pieces 36 alternate, i.e. pole pole of one polarity is surrounded by junction tips of opposite polarity.

Between the pole pieces 36 there are end gaps lying in three mutually orthogonal planes. On the axial gap lines, there are twelve measuring electrodes (figure 2). The measuring electrodes I-I2 are installed opposite the middle of the sides of the pole pieces 36, the gaps are filled with dielectric, and the pole pieces are protected from the outside by a spherical casing 37 (figure 2) made of a dielectric material.

Each four subtracting amplifiers, two addition units and a subtraction unit serve to measure one of the three components of the flow velocity vector along the axes coming through the intersection points of the annular gaps of the primary measuring transducer.

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To measure the component of the flow velocity along the X axis to the subtractive amplifiers 13-16 (Fig. 1)

Electrode pairs are connected that are not lying in a plane perpendicular to the X axis and adjacent to pole pieces having a polarity S (Fig. 3-5). Wherein

electrodes 2 and 4 located in

a vertical annular gap to the right of the plane perpendicular to the X axis (FIG. 4) is connected to the inverting inputs of amplifiers 13 and 14; electrodes 10 and 12, located in the same e (vertical) annular gap, but to the left of the utsazannaya. plane, are connected to non-inverting inputs of amplifiers 15 and 16. Electrodes 1 and 3,

mounted in another (horizontal) annular gap to the plane perpendicular to the X axis (Fig. 3), are connected to non-inverting inputs of amplifiers 13 and 14, and electrodes 9 and

11, installed in the same (horizontal) annular gap, but beyond the specified plane, are connected to the inverting inputs of amplifiers 15 and 16.

The outputs of the amplifiers 13 and 14 are connected to the inputs of the adding unit 25, the output of which is ss (the same as the inverting input of the subtracting unit 31. The outputs of the amplifiers 15 and 16 are connected to

the inputs of the adding unit 26, the output of which is fed to the non-inverting input of the subtracting unit 31.

To measure the components of the flow velocity along the if.Z axes, pairs of electrodes are used adjacent to pole pieces of the same polarity (S) and connected to the corresponding amplifiers in the same way as described.

When measuring, the primary measuring transducer is placed in the flow, Dp of convenience of orientation, it can be fixed in the flow frame, for example, as shown in Fig.6. The electronic unit is connected to the primary measuring transducer by means of a connecting cable.

A device for measuring the flow rate of an electrically conductive liquid works as follows.

The primary measuring transducer placed in the test medium is affected by the flow of an electrically conducting fluid.

In an electrically conducting fluid moving in a magnetic field created by

in the gaps of the converter’s magnetic system, induce an emf whose value is proportional to the flow velocity and the magnetic field strength.

Under the condition of a laminar flow around the transducer by the fluid flow Vy, the location of the flow velocity vectors relative to the magnetic field strength vectors at the points of location of the measuring electrodes is shown in FIG.

Thus, at the outputs of the electronic unit (addition blocks 31–33), three voltages are simultaneously present, the values of which are proportional to the values of the projections of the velocity vector, the flow of electrically conductive fluid on the coordinate axes of the primary measuring converter (drawn through the intersection points of the axial lines of three orthogonal annular gaps), which determine the direction and magnitude of the flow velocity vector, the direction of which is arbitrary in the coordinate system

converter

Claims (1)

Claims An apparatus for measuring the flow rate of an electrically conductive fluid. - W 20 25 zo 35 55 containing a primary measuring transducer with a magnetic system in the form of a rotational body with alternating poles and symmetrical gaps, in which are located measuring electrodes connected to an intermediate measuring transducer consisting of an addition unit and two subtraction blocks, characterized in that measurements of the flow velocity vector and sensitivity, the magnetic system of the primary measuring transducer is made in the form of four intersecting days, part of the core magnetic conductors with four two-section excitation coils and eight pole tips having the form of equilateral spherical equal triangles, the measuring electrodes are installed opposite the midpoints of the pole tips in the middle of the annular gap, and twelve subtractive amplifiers are additionally inserted into the intermediate measuring transducer, twelve addition units and a subtraction unit, with four subtracting amplifiers, two addition units and a subtracting unit forming one From the three measuring channels of the intermediate converter, and in each measuring channel, to each subtractive amplifier are connected pairs of electrodes adjacent to pole tips of one polarity and located outside the plane perpendicular to the corresponding measuring axis, with electrodes located in the annular gap on one side specified plane connected to the inverting inputs of the first and second subtractive amplifiers, and the electrodes installed in the same annular gap on the other side of the decree connected to the non-inverting inputs of the third and fourth subtractive amplifiers, the outputs of the first and second subtractive amplifiers are connected to the inputs of the first of every two addition blocks, the outputs of the third and fourth subtractive amplifiers to the inputs of the second of two addition blocks, whose outputs are connected to the input block nychitani. nepSvwbiLL i / 3MepLfrneMffd / u npeo pojoecrrfe b Emé / G77rody 1 2 3 5 6 7 8 9W7JJZ Knocked out - Sflojfu Sb / i / u blocks J / ± wow J / tVy 1 hp Jj tVz figure 1 35 V - eight 72 FIG 5 FIG. 6 Numofftfff block Compiled by Yu.Mruchko Editor N.Kishtulinets Tehred A. Kravchuk Order 772/47 Circulation 777 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, Projecto st., 4 7 Proofreader A.Zimokosov