SU1265478A1 - Correlation flowmeter - Google Patents

Abstract

The invention relates to instrumentation engineering and reduces the measurement error. The device contains two primary converters 1 and 2, the modulated signals of which are fed through switch 5 to detectors 6 and 7 and through switch 10 to calculation unit 15. Connecting to each primary converter 1 and 2 of each detector 6 and 7 an even number of times that, the systematic error at each connection will be alternating and the total measurement error will vanish. 1 pe. (Ls

Description

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The invention relates to instrument engineering and can be used in instruments for measuring the flow rate and velocity of various media.

The aim of the invention is to reduce the measurement error.

The drawing shows a structural diagram of a correlation flowmeter.

The correlation flow meter contains two primary transducers 1 and 2 fluctuations of the flow characteristics, the outputs of which are connected to information inputs 3 and 4 of the first switch 5, two detectors 6 and 7 flow fluctuations, the inputs of which are connected to the outputs 8 and 9 of the first switch 5; the second switch 10, the inputs 11 and 12 of which are connected to the outputs of the detectors 6 and 7 of the flow fluctuations, and the outputs of the detectors 6. and 7 of the flow fluctuations - with the inputs 13 and 14 of the calculation unit 15; timer 16, the output of which is connected to the control inputs 17 and 18 of the switches, respectively, 5 and 10.

The correlation flow meter operates as follows.

During flow through the conduit, the transducers 1 and 2 detect disturbances in the 1NII state of the fluid, and modulated signals appear, for example, in phase or frequency. Then, if the output of the timer is voltage Log.1, then the signal from the output of the primary converter 1 enters input 3 and through switch 5 into detector 6, from the output of which through input 11 of switch 10 enters input 13 of calculation unit 15, and the signal from the output of the primary converter 2 is fed through the input 4 of the switch 5 to the input of the detector 7, from the output of which is fed through the input 12 of the switch 10 to the input 14 of the calculating unit 15.

If the output of the timer 16 is voltage Log.O, the signal from the output of the primary converter 1 is fed through the switch 5 to the input of the detector 7, the output of which enters the input 12 of the switch 10 to the input 13 of the calculator 15 and the signal from the output of the primary converter 2 It is fed through the input 4 of the switch 5 to the input of the detector 6, from the output of which is fed through the input 11 of the switch 1U to the input 14 of the computing unit 15.

Suppose that the detector 7 delay time is longer than the detector 6 by the value of S. Then, if the signal from the primary converter 1

enters the calculation unit 15 through the detector 6, and the signal from the primary converter 2 through the detector 7, the transport lag time is determined with an error of +0, which

corresponds to a certain error + p when determining the flow rate. If the signal from the primary converter 1 enters the calculation block 15 through the detector 7, and the signal from the primary converter 2 passes through the detector 6, the transport delay time is determined by the error

-S that corresponds to the error

-p when determining the flow. At the end of the course of the control unit control sig

The waves represent a sequence of square-wave pulses, in which the duration of a Log.O is equal to the duration of a Log.1 with an equal number of

5 Log.O and Log.1. I

The determination of the transport delay time occurs as a result of the integration operation over time, and the error is integrated. Since the error represents an alternating function that takes two values + S and –5, the resulting systematic component of the measurement error tends to zero when integrating.

Introducing the timer and switches into the correlation flow meter will improve the measurement accuracy and expand the scope.

Claims (1)

Invention Formula A correlation flowmeter consisting of two primary transducers fluctuating the flow characteristics located on a fixed distribution. standing apart from each other, the first switch, two flux fluctuation detectors, a computing unit and a timer, characterized in that, in order to reduce the error. measurements, it includes a second switch, with the outputs of the first and second primary converters 5 are connected respectively to the first and second inputs of the first switch, the outputs of which are connected to the inputs of the flow fluctuation detectors, vy312654784 The first and second detectors moves each of the two outputs of the last flow fluctuation are connected respectively to the inputs of the calculating unit, to the first and second information, the control input of each switching inputs of the second switch, the torus, is connected to the timer output