SU1753282A1 - Method of determining multi-phase liquid flow rate - Google Patents

Abstract

Use: for determining the flow rates of various phases of a multi-phase fluid. SUMMARY OF THE INVENTION: With the aid of a transmitting array 3 from a veto of diodes 4 and a receiving array 5 of photodiodes 6, the flux is visualized in transmitted light. The dimensions of the flow in the direction of transmission are limited by the transparent screens 2. The separation of images of the individual phases of the flow is carried out according to the different intensity of their traces in the visualized image of the flow. The total sum of the areas of the individual elements of the structural phases of the liquid gives information about the flow rate of each phase of the liquid. 4 il.

Description

figure 1

The invention relates to a measurement technique and can be used to determine the flow rate of a fluid in a well in the oil industry.

A known method of measuring flow rate by visualizing the structure of the flow in scattered light using imaging particles and determining the total area of the particle tracks by which flow is judged.

The disadvantage of the method is that it cannot be used to measure the flow rates of the various phases of the multiphase flow.

The closest is the method of determining the flow rate of a multiphase fluid, which consists in visualizing the flow structure, in a given volume and measuring the total area of images of individual elements of structural phases in the visualized flow image.

The disadvantage of the prototype is the limited information capacity in the case of measuring the flow rate of one liquid phase.

The aim of the invention is to expand the information capabilities of the method by simultaneously determining the flow rates of the various phases of the liquid.

The goal is achieved by the fact that in the method of determining the flow rate of a multiphase fluid, which consists in visualizing the flow structure in a given volume and measuring the total area of the images of the structural phases in the visualized flow image, which determines the flow rate, form a certain flow size in the direction orthogonal to the visualization plane , and the visualization of the flow structure in a given volume is carried out in transmitted light, while the separation of images of individual phases of the liquid is carried out according to different inte the traits of their traces in the visualized image of the stream.

The implementation of the method is presented on the example of a water-oil flow meter.

FIG. 1 and 2 are a diagram of the device, explaining the principle of the method; in fig. 3 is a diagram of the downhole part of the gauge; in fig. 4 is a diagram of the ground part of the meter. with/

The device comprises a housing 1 in which parallel screens 2 are installed, behind one of which is a transmitting matrix 3, made of infrared emitting (IR) LEDs 4, and behind an opposite matrix receiving 5, made of photodiodes 6.

In the ground part of the device there is a screen for visual observation - LED5, one matrix, indicator 7 (Fig. 2).

The downhole device (Fig. 3) contains a pulse counter 8, the counting input of which is connected to the conductor AND cable through diode 9. The low-order outputs of counter 8 are connected to the input of the decoder 10 lines, the outputs of the decoder 10 lines are connected to the control inputs of the transmitting transistor switches part 11, as well as to the inputs of the transistor switches of the receiving part 12.

5 The input of the transistor switches of the transmitting part 11 is connected via a ballast resistor 13 to the core of the cable. The outputs of the transistor switches of the transmitting part 11 are connected to the corresponding lines

0 of the transmitting matrix 3. The inputs of the transistor switches of the receiving part 12 are connected to the corresponding rows of the receiving matrix 5. The output of the transistor switches of the receiving part 12 is connected to the input of the amplifier

5 14, the output of which is connected to the residential ill cable. The outputs of the higher bits of the counter 8 are connected to the input of the decoder 15 columns, the outputs of which are connected to the columns of the transmitting matrix 3 and the receiving

0 matrix 5. At the same time, the first output of the decoder of 15 columns is connected to the first column of the transmitting matrix 3 and the first column of the receiving matrix 5 and so on, respectively. The cable core I i is also connected via a diode 16 to the input of the shaper 17 of the reset pulse, the output of which is connected to the zeroing input of the counter 8.

The ground-based instrument (Fig. 4) contains a pulse generator 18, the output of which is p0 keys to the input of the pulse counter 19 and to the input of the pulse former 20. The outputs of the lower bits of the pulse counter 19 are connected to the inputs of the decoder 21 lines, the outputs of which are connected to the equalizing inputs of transistor switches 22. transistor switches 22 are connected to the output of amplifier 23, and the input of amplifier 23 is connected to core III of the cable. The outputs of the transistor switches 22 are connected to the rows of the LED matrix indicator 7. At the same time, the first output of the transistor switches 22 is connected to the first row and then in order. The outputs of the high bits of the counter 19 pulses are connected to the inputs of the decoder 24 columns, the outputs of the decoder 24 columns are connected to the corresponding columns of the indicator matrix 7, the first one. 24 columns decoder output connected

to the first column and further in order. The first output of the decoder is 21 lines (i.e., the output whose active state corresponds to the zero state of the lower bits of counter 19 is connected to one of the inputs of the matching circuit 25, zero, the first input of the decoder 25 of columns is connected to another input of the matching circuit 25. The output 25 of the coincidence circuit of zeros is connected to the input of the pulse shaper 20, the output of the pulse shaper 20 is connected to the conductor II of the cable, the conductor I of the cable is connected to the positive-1 link of the power supply (not shown).

The scheme works as follows.

From the pulse generator 18, the positive polarity impulses through the core of cable II are transferred to a binary counter 8 having log2N + logaM bits (each term should be rounded up to an integer). The younger log2N bits are applied to the decoder 10 lines, and the older bits to the decoder 15 columns. When the counter 8 is set to zero, there is a ground potential at the first output of the 15 column decoder, so the first column of the receiving 5 and transmitting 3 matrices is connected to the grounded pole of the power supply. Each output of the decoder 10 lines is connected to the control input of two keys, one of which is included in the transistor switches of the transmitting part 11, and the other - the receiving part 12. The keys 11 and 12 connect the lines of the transmitting matrix 2, respectively, through a resistor 13 to the ballast power supply, and the receiving array 5 rows to the amplifier 14. When the counter 8 is zero, the row decoder has a logical O signal at the first output, which, including the 10 lines corresponding to the first output of the decoder, connects the first line of the transmitting signal Atrits 3 to the power supply source, and the first row of the receiving matrix 5 to the amplifier 14. Therefore, the LED 4 turned on at the intersection of the first row and the first column of the transmitting matrix 3 is connected to the power supply, and the photodiode 6 turned on the intersection of the first row and the first column of the receiving matrix 5 is connected to the amplifier 14.

With the arrival of clock pulses at the input of the counter of 8 pulses, the state of the least significant bits will change in the direction of increasing, and at the outputs of the 10-line decoder a logical O signal will appear sequentially (at the second output, then at the third, and so on). in order). Accordingly, the transistor switches 11 will switch

plus a power supply from the first row to the second, and so on, in order, and the transistor switches 12 will synchronously switch the input of the amplifier 14 from one row of the receiving matrix 12 to another in order. When the number of clock pulses exceeds (the number of rows), the state of the most significant bits will increase by one, and the lower bits will reset to zero, and at the output of the decoder 15 columns a log. O will move from the first output to the second, and transistor switches 11 and 12 will reconnect the first row. Then, in the process of counting the pulses, the rows will again switch sequentially to the Nth row, but since the decoder of 15 columns switched ground from the first to the second column, another line of LEDs 4 and photodiodes 6 corresponding to the second column will be involved.

Thus, with further counting of pulses, a decoder of 15 columns and transistor switches 11 and 12 with a decoder of 10 rows will sequentially connect LEDs 4 and photodiodes of matrix 3 and 5, respectively, to the power supply and to the input of amplifier 14. and the Mth column, and with the arrival of the next pulse, the counter 8 is zeroed out, and the process is repeated from the beginning.

In order to synchronize the operation of the downhole and surface instruments, a reset generator 17 is provided. When a negative pulse is applied to the conductor II cable, the reset driver 17 supplies a pulse to the input of the zero setting of the counter 8.

Ground instrument (Fig. 4) works as follows

The part of the circuit, containing a pulse counter 19, a decoder of 21 rows, a decoder of 24 columns, transistor switches 22, and an LED matrix indicator 7, operates similarly to the corresponding part of the downhole tool circuit. Counters 8 and 19 pulses count pulses of one generator 18 pulses. In order for the states of the counters 8 and 19 to coincide, the counter 8 is reset to zero when the counter 19 arrives at the zero state. When the counter 19 is zero, the first output of the decoder of 21 rows and the first output of the decoder of 24 columns have a signal log, O. This the state is fixed by the circuit 25 of coincidence of zeros, which, sends a signal to the driver of the pulse 20, which, in turn, generates a negative pulse on the core II of the cable. In the downhole tool, this pulse sets the counter 8 to the zero state. With

In the absence of a signal from the zero-coincidence circuit 25, the pulse former 20 transmits pulses of the generator 18 to the core II of the cable in positive polarity.

The signal from cable core III, the level of which is determined by the photocurrent level of the photodiode 6, which is currently connected to the amplifier 14 of the downhole tool, is fed to the amplifier 23. This amplifier amplifies the signal to a level sufficient to illuminate the LEDs 26 of the matrix indicator 7,

The principle of operation of the device consists in sequential and synchronous switching of the LEDs 4 of the transmitting matrix 3, photodiodes b of the receiving matrix 5 and the LEDs 26 of the matrix indicator 7. Therefore, recording the transparency of the space between the matrices 3 and 5 at this point is discrete. To eliminate this discreteness, choose the frequency switching LEDs and photodiodes, based on the following considerations,

If we take the maximum speed of the non-uniformity of the aodon-oil mixture in the slit gap between the transmitting 3 and the receiving 5 matrices equal to V, while moving this non-uniformity to a distance equal to the distance between neighboring LEDs in the matrix is

-I where S is the distance between adjacent LEDs in the array.

During the time t it is necessary to make a full survey of all photo and LED matrices one or more times. Hence the frequency of the survey

t

The frequency of the pulse generator 18 is determined from the formula

fonp - f - IP

IT3KT

VMN S

where M is the number of columns m CTR1;

N is the number of rows of matrices.

The distance between the screens 2 is determined on the basis of the estimated range of the measured velocities, the viscosity of the oil, the required measurement accuracy, and the presence and size of solid particles.

The information reproduced on the LED matrix indicator 7 can be recorded by a movie camera. In this case, we obtain a complete picture of the movement of fluid in the well.

After stripping, the flow rate can be determined as follows.

If on screen 2 you put a risk (perpendicular to the flow), then on the film in each frame this risk will also be visible, with respect to which you can record the movement of structural elements.

Suppose that at some part of the film of length L (the distance between the risks in the part of the film at which the displacement of the elements was determined), it was determined that a certain amount of oil S, oil, and water S,

At the same time measurement

T-L

Uplenki

where Efilki is the speed of the film flow.

The amount of oil that has passed through the cross-section at risk in time T,

Otsr reti oneft N K,

where H is the distance between the screens 2; K - coefficient taking into account the increase (decrease) of the screen 2 in the film frame.

Consumption

f. Unneft. Onefti,

U T

The greater the L, i.e., the longer the measurement time T, the more accurate. You can determine the flow.

Claims (1)

The invention The method of determining the flow rate of a multiphase fluid, which consists in visualizing the flow structure in a fixed volume and measurement of the total area of images of individual elements of the structural phases in the visualized flow image, according to which the flow rate is judged, characterized in that expanding information capabilities by simultaneously determining the flow rates of various liquid phases, pre-form a fixed flow size in the orthogonal direction the visualization plane, and the visualization of the flow pattern is carried out in transmitted light, while the separation of images of individual phases of the liquid is carried out according to different intensity of their traces in the visualized flow image. ABOUT water with zpp 31 -Kb il mzd hv.- / 9i /% |: wnu wjnft DUDh & Vy epschraik P  / U five s t 1ШШЩЩГШЩ WQKtfevdanmdDwj Qi L e // 3SO / ; FDf / EPGGSCH tmyomkhepnachshyyik .with eleven ff f r1 I t / & c 4L fl n spy S8SCSil JKUAU a stop num. FIG C