RU2003944C1 - Ultrasonic flowmeter - Google Patents

Description

which, through amplifier 4 and emitter 5, enters a moving medium. Reflected from moving particles, the acoustic signal is fed to the input of the receiving element 7.

b (t) -Aa (1+) t-re

2 V

NUM - A exp {- B -t - (ge - rz)} x

/ 2V

X (-t - (Ge - G3),

2 V

R2 (t) Az exp {- B -1 - (ge - ge) G x

where V is the particle velocity;

c is the speed of light;

tv is the propagation time of the acoustic signal from radiation to reception.

Equation (3) shows that the received signal corresponds in shape to the emitted but delayed in the acoustic channel. At the same time, the emitted signal a (t) is delayed by the adjustable delay unit 9 by the time ge:

d (t) a (t-r3). (4)

. The signals e (t) and d (t) simultaneously arrive at the two inputs of the correlator 12 and through the phase shifters 10 and 12 through 90 ° to the two inputs of the correlator 13. At the outputs of the correlators 12 and 13, voltages are generated

Ri (t) A exp {- B ЈЈ.t - (Te - r3)} x, 2V

X COS fflo (- t - (Ge - G3),

2V

R2 (t) A exp {- B -t - (re - T3)} x

, 2V

X sin ftfe (-1 - (Te - G3),

(5)

which go to the inputs of the quadrants 14 and 15 respectively. At the outputs of the latter, voltages are formed:

Claims (1)

The claims ULTRASONIC FLOWMETER containing a white noise generator, a modulator, the second input of which is connected to the output of the harmonic oscillator, a first amplifier and emitter, as well as a receiver element, a second amplifier and a first correlator, the second input of which is connected through an adjustable delay unit with the output of the modulator, characterized in that, with the aim of I. increasing the accuracy of measurement, into it / 2 V X Sir / fife (-Ј- t - (Ge - Gz). (6) which go to the two inputs of the adder 16. At the output of the last voltage is generated R2 (t) Ri2 (t) + R22 (t) 12 (7) A2exp {-vЈU-g- (ge-g3)} This voltage is fed to the input of the square root extraction unit 17, at the output of which a voltage is generated R (t) - A exp {- B -1 - (ge - G3)} 2, (8) in which there is no high-frequency filling, that is, there is no dependence on the carrier frequency. Thus, the proposed flowmeter in comparison with the prototype provides an increase in the accuracy of measuring the speed of moving particles in a pipeline of a given range. This is achieved by autocorrelation quadrature processing of acoustic signals. (56) Khamidullin V.K. Ultrasonic measuring devices and system. L .: Engineering, 1989, p. 176, fig. 3.22. the first and second phase shifters, the second correlator, the first and second quadrators, the adder and the square root extractor are introduced, and the first phase shifter, the second correlator, the second input of which is connected to the output of the adjustable delay unit through the second phase shifter, are connected in series to the output of the second amplifier a quadrator, an adder, the second input of which is connected through the first quadrator to the output of the first correlator, and a square root extraction unit.