SU1582104A1 - Apparatus for conductometric measuring - Google Patents

Abstract

The invention relates to hydrophysical analysis and is intended to measure the concentration and density of electrolyte solutions by an indirect method. The purpose of the invention is to improve the measurement accuracy. The device consists of a housing on which a central electrode is installed, insulated, except for the end part, by an insulator. A layer of metal is applied to the open surface of the central electrode. An external electrode is installed on the body in the form of a spiral, covering the measuring area around the central electrode. A thermosensitive microwire is placed in the inner cavity of the outer electrode; the free space is filled with a thermally conducting insulating medium. In operation, a measurement is made of the resistance between the electrodes and the temperature of the medium, equal to the sum of the temperatures of the thermocouple and the thermal resistance, from which the required parameter, such as concentration, is calculated using known algorithms. 2 Il.

Description

(21) 4337079 / 25-25

(22) 10/30/87

(46) 07/30/90. Bul Number 28

(72) V.I. Levtsov, A.I. Korolev

and G. A. Myskin

(53) 543.247 (088.8)

(56) Gibson G. H. and Schwarz W. H. Detection of conductivities by fluctuation turbulent field.-J. Fluid Meeh, v. 16, pt. 3, 1963, p. 375.

USSR Author's Certificate No. 1157433, cl. G 01 N 27/12, 1985.

(54) DEVICE FOR CONDUCTOMETRIC MEASUREMENTS

(57) The invention relates to hydrophysical analysis and is intended to measure the concentration and density of electrolyte solutions by an indirect method. The purpose of the invention is to improve the measurement accuracy.

The device consists of a housing on which a central electrode is installed, insulated, except for the end part, by an insulator. A layer of metal is applied to the open surface of the central electrode. An external electrode is installed on the body in the form of a spiral, covering the measuring area around the central electrode. A thermosensitive microwire is placed in the internal cavity of the external electrode, the free space is filled with a thermally conducting insulating medium. In operation, the resistance between the electrodes and the temperature of the medium are measured, which is equal to the sum of the temperatures of the thermocouple and the thermal resistance, from which the required parameter is calculated, for example, the concentration according to known algorithms. 2 Il.

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The invention relates to hydrophysical measurements and is intended to measure electrolyte parameters, such as seawater, such as salinity, density, concentration of dissolved salts, reduced electrical conductivity by an indirect method.

The aim of the invention is to improve the measurement accuracy.

FIG. 1 shows the structure of the device; in fig. 2 - dynamic characteristics of the sensor.

The device consists of a housing 1 on which a central electrode 2 is installed, insulated, apart from the end part, from the external environment and the housing 1 by an insulator 3. A layer of corrosion-resistant metal is applied to the projecting open surface of the central electrode 2, that is, to its end part. 4, the output 5 from which through the insulator 3 passes into the housing 1. On the housing 1 there is an external electrode 6 in the form of a spiral, covering the measurement area around the central electrode 2. The external electrode 6 is made of a metal tube, into the internal second cavity which houses the metal microwire thermosensitive 7, wherein both ends of the tube are rigidly fixed in the housing 1. The free space inside the tube cavity filled termoprovod conductive electrically insulating liquid 8 /

The terminals of the electrical elements (central and external electrodes), the coating of the electrode (thermocouple), the thermosensitive microwire are connected to the corresponding amplifiers in the electrical circuit of the device, where 9 is the amplifier of the first temperature signal (thermocouple), 10 is the conductivity signal amplifier, 11 is the USSP

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A second temperature signal (thermal resistance). The outputs of the amplifiers 9 and 11 are summed and normalized with a factor of 0.5 in the adder 12, after which they are fed to the first input of the computing device. The second and third inputs of the computing device receive signals from the outputs of amplifiers 10 and 11.

The device works as follows.

The central 2 and external 6 electrodes are connected to the AC circuit of the amplifier 10, the output DC voltage is fed to the input of the computing device.

temperature, almost completely coherent signal conductivity.

Claims (2)

 1. A device for conductometric measurements, containing a conductometric sensor consisting of external and central electrodes, a computing device, amplifiers, a layer of corrosion-resistant metal is applied to the surface of the central electrode, forming a thermocouple with the material of the central electrode, the first of which are connected to electrodes conductometric sensor, and The terminals of the central electrode 1 and the second are connected to a thermocouple, characterized in that, in order to improve the measurement accuracy, an amplifier and an adder are added to it, and the external electrode of the conductometric sensor is made of a metal tube in the form of a spiral 20 which contains a resistance thermometer connected to the input of an additional amplifier, the output of which is connected to one of the inputs of the adder, the second input of which is connected to the output of the second amplifier, and Covers 4 are included in the direct current circuit of amplifier 9, the output voltage of which is proportional to the surface temperature of the contact, the central electrode - the coating, provided that the thermocouple contacts are cold or thermostated. Thermal resistance pins are included in the DC circuit of amplifier 11, the output voltage of which is therefore approximately proportional to the average of the top 25 outputs of the first, additional amplifiers of the cylindrical volume and adder respectively connected to the medium bounded by coil 6. The output of the first, second and third The inputs of the computations of amplifiers 9 and 1 are summed from the relative device. corresponding to the real temperature 2. The device according to claim 1, characterized in in the adder 12. As a result, the diameter of the outer electrode is 5 - the output of the adder 12 generates a signal of 10 the diameters of the central electrode. temperature, almost completely coherent signal conductivity. Invention Formula 1. A device for conductometric measurements, containing a conductometric sensor consisting of external and central electrodes, a computing device, amplifiers, a layer of corrosion-resistant metal is applied to the surface of the central electrode, forming a thermocouple with the material of the central electrode, the first of which are connected to electrodes conductometric sensor, and srig.1 FIG. 2