SU1679338A1 - Device for measuring turbulence parameters in a flow of conducting liquid - Google Patents

Abstract

The invention relates to analytical instrumentation and can be used for problems of oceanology. The purpose of the invention is to expand the functionality of the device for measuring the parameters of the turbulence of the flow of an electrically conductive liquid due to joint measurements in one sensitive area of pulsations of the flow velocity and conductivity. This is accomplished through the implementation of a primary converter that implements both magnetodynamic and conductometric measurement methods. Further, the device implements frequency separation of signals proportional to two hydrophysical characteristics of the medium, pulsations of the flow rate of an electrically conductive fluid and conductivity, the separation is performed by a system of filters and synchronous detection at certain phase relationships. 2 Il.

Description

The invention relates to the field of analysis of liquid media and can be used in experimental hydrodynamics to determine turbulence parameters, in oceanology to measure the velocity of an electrically conductive fluid and electrical conductivity in one sensitive area of pulsations and to study the fine structure of ocean waters.

The aim of the invention is to expand the functionality of the device due to joint measurements in a single sensitive area of pulsation of the flow velocity and conductivity.

FIG. 1 shows the design of a primary converter (PP); Fig. 2 is a block diagram of a device for measuring parameters of turbulence of a flow of an electrically conductive liquid.

The device contains a permanent magnet 1, covered with dielectric-2, PP made in the form of a body of rotation. In the transverse gap of the pump part of the PP, symmetrically with respect to the axis of symmetry, there are pairwise measuring 3 and 4 and current 5 and 6 electrodes (figure 2). The device contains a differential amplifier (RC) 7, a pump filter (PF) 8, the first low-pass filter 9 (LPF), the source 10 of the reference

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ABOUT)

with

tension, first synchronous detector (SD) 11, dumator 12, controller 13, comparator 14, second synchronous detector (SD) 15, second low pass filter 16, selective amplifier 17, voltage-current converter 18, controlled oscillator Sh. Low-pass filter 9, low-pass filter 16 and selective amplifier 17 are the first, second and third outputs of the device, respectively. The measuring electrodes 3 and 4 are connected to the inputs of the remote control unit 7, the output of which is connected to the input of the low-pass filter 9 and the PF 8 to the input of the first LED 11. The inputs of the adder 12 are connected to the output of the LED 11 and the source 10, respectively, of the reference voltage 13 is connected to the control input of the generator 19, the output of which is connected to the input of the converter 18, the input of the LED 15 and through the comparator 14 to the reference inputs of the LED 11 and the LED 15. The outputs of the converter 18 are connected to the current electrodes 5 and 6, the Output of the LED 15 is connected to the input of the low pass filter 16 and the selective amplifier 17.

The device works as follows.

The current electrodes 5 and 6 from the two outputs of the converter 18 are supplied with a sinusoidal alternating current 1, the value of which is determined by the following relation: Uig / R, where Uig is the output voltage of the controlled oscillator 19; R is a voltage-current converter resistor 18. The control unit 7 measures and amplifies KI times the potential difference of the measuring electrodes 3 and 4. The output voltage U of the control unit 7 is determined by the ratio

U I (PF + 1) / 0wc) Ki + KiKnp V4, (1) where is the resistance of the electrolyte solution between the current electrolytes; C is the total capacitance of the electrical double layer of current electrodes; co-frequency output voltage of generator 19; CRC is the coefficient for converting the pulsation of the speed V1 to the voltage. To isolate the second component, the first LPF 9 is used, which amplifies this component K2 times. The signal Ug is directly proportional to the pulsations of the flow rate 2 of the electrically conductive fluid, determined by the ratio

Ug Ki feKnp V1, - (2)

FS 9 is tuned to the frequency of the output voltage of the generator 19. Its output voltage Us is defined as follows:

Ue l (Rx + 1) / ()) KiK3, (3)

where Cs is the gain of the bandpass filter 8.

The first synchronous detector 11 detects the output voltage Ua. Since the input signal from comparator 14 to the reference input of the first synchronous detector 11 coincides in phase with the output voltage Uig of the generator 19, the unipolar output voltage Un of the first synchronous detector 11 is determined by the relation

Un GRJKgKz (4)

The adder 12 performs the summation of the unipolar output voltages Un and Uio, respectively, of the first synchronous detector; 11 and reference source 10. Its output voltage Ui2 is determined by the ratio

Ui2 Uio-MJigR Ki Kz / R. (5)

The proportional-integral regulator 13 continuously adjusts the output voltage Dig of the generator 19 in such a way as to keep the output voltage Ui2 of the adder to zero. Therefore, the output voltage Dig of the controlled oscillator 19 is determined by the ratio

.U th R, „

IJ19 (6)

where A is the conductive constant of the electrical conductivity converter;

) f - the value of specific electrical conductivity.

The second synchronous detector 15 detects the output voltage U19. Its output voltage is directly proportional to the instantaneous values of the specific electrical conductivity of. The second FMP 16 selects and amplifies K4 times the average values of 5 electrical conductivity. Its output voltage UIG is determined by the ratio Uio R K Ј

Uie

(7)

Ki CCA

The selective amplifier 17 selects and amplifies, in KB, pulsations of 1 specific electrical conductivity. Its output voltage Ui is determined by the ratio

Ur / UioR Kg

(eight)

Claims (1)

Ki K3 A From relations (2) and (8), it can be seen that the output signals of flow rate pulsations and specific electric conductivity pulsations do not depend on each other. The invention of the device for measuring the parameters of the turbulence of the flow of electrically conductive a fluid consisting of a four-electrode primary transducer with two current and two measuring electrodes of a differential amplifier, whose inputs are connected to the measuring electrodes, first and second synchronous detectors, and a voltage-current converter, the output of which is connected to the first current electrode that differs in that, in order to expand the functionality of the device, the primary converter is made in the form of a body of rotation of a dielectric-coated permanent magnet, in the transverse Azora nose portion which symmetrically relative to the symmetry axis electrodes are arranged in pairs, wherein the external electrodes are measuring and internal - current, introduced into the apparatus first and second low pass filters, band pass filter, reference source HA direct voltage, an adder, a comparator regulator 0 five 0 a torus, a selective amplifier and a control oscillator, the output of the differential amplifier is connected to the input of the first synchronous detector through a band-pass filter and to the first low-pass filter, the output of which is the first output of the device, the inputs of the adder are connected respectively to the output of the first synchronous detector and the source of the reference voltage the output of the adder through the regulator is connected to the control input of the generator. Its output is connected to the input of the voltage-current converter, the input of the second synchronous the detector and a comparator with reference inputs of the first and second synchronous detectors. The second output of the voltage-current converter is connected to the second current electrode. And the output of the second synchronous detector is connected to the inputs of the second low-pass filter. Low frequency and selective amplifier whose outputs are respectively the second and third outputs of the device. FIG. FIG. 2 / 7