CN110631958A - Gas-liquid two-phase flow parameter measuring method - Google Patents
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Abstract
The invention belongs to the technical field of flow detection, and relates to a gas-liquid two-phase flow parameter measuring method, which adopts an ultrasonic measuring unit and a differential pressure measuring unit to measure the parameters of the gas-liquid two-phase flow in a pipeline, and introduces a dynamic wave storage and dynamic time delay mechanism under the measurement of a two-phase medium, thereby solving the problem of incomplete acquired echo signals caused by large difference of sound wave propagation speeds of ultrasonic waves in the gas-phase medium and the liquid-phase medium in the existing sampling mechanism; then according to the collected ultrasonic echo signal, the uplink and downlink time difference delta t and the uplink time t are measuredupTime of downlink tdownAnd calculating, and further calculating to obtain each parameter of the gas-liquid two-phase medium by a measuring method combining an ultrasonic measuring principle and a differential pressure type measuring principle, and the method has the advantages of no radioactive pollution, reliable and stable measuring result and the like.
Description
Technical Field
The invention belongs to the technical field of flow detection, relates to ultrasonic flow measurement and differential pressure type flow measurement, and particularly relates to a gas-liquid two-phase flow parameter measurement method.
Background
The gas-liquid two-phase flow is widely applied to the industrial fields of petroleum, chemical engineering and the like, and the parameter measurement difficulty of the gas-liquid two-phase flow is large compared with that of the single-phase flow due to the diversity and variability of the distribution conditions of the gas-liquid two-phase flow.
The traditional method for effectively measuring the gas-liquid two-phase flow mostly adopts a separation type measurement method, wherein a gas phase and a liquid phase are separated to form a single-phase fluid after separation, and then the gas phase and the liquid phase are respectively measured by adopting a single-phase fluid measurement method, and the separation type measurement method has the advantages of large volume, high cost and incapability of measuring the gas-liquid two-phase flow parameters in real time. The gamma ray measurement method has a complex structure and high cost, and can generate radioactive pollution, so that the wide application of the measurement method is limited. Therefore, the development of a gas-liquid two-phase flowmeter suitable for engineering application is of great significance.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a gas-liquid two-phase flow parameter measuring method, which utilizes the fusion of an ultrasonic measuring technology and a differential pressure measuring technology and introduces a dynamic wave storage and dynamic time delay wave storage mechanism to measure the gas-liquid two-phase flow parameters.
In order to achieve the purpose, the invention provides the following technical scheme:
the method for measuring the parameters of the gas-liquid two-phase flow simultaneously adopts an ultrasonic measuring unit and a differential pressure measuring unit to measure the parameters of the gas-liquid two-phase flow in a pipeline, and introduces a dynamic wave storage and dynamic time delay mechanism under the measurement of a two-phase medium, and specifically comprises the following steps: taking the state when the two-phase medium is pure gas as the initial state of a dynamic wave storage and dynamic time delay mechanism, in pure gas, after an ultrasonic excitation signal is sent, carrying out time delay and then starting to collect an echo signal, and storing a static ultrasonic echo signal at zero flow; judging whether an ultrasonic echo signal is acquired or not under a two-phase medium, and if the ultrasonic echo signal is acquired, not starting a dynamic wave storage and dynamic time delay mechanism; if the ultrasonic echo signal is not acquired, starting a dynamic wave storage and dynamic time delay mechanism; and calculating according to the structural parameters, the medium parameters, the acquired ultrasonic echo signals and the differential pressure signals to obtain all parameters of the gas-liquid two-phase flow.
Further, the method for measuring the gas-liquid two-phase flow parameters specifically comprises the following steps:
step 1), defining initial time t for starting to acquire ultrasonic echo signalsdelay＝tdelay1，tdelay1Initial time to start acquiring ultrasonic echo signals for pure gas based on the initial time tdelay1Starting to acquire ultrasonic echo signals, and storing static ultrasonic echo signals at zero flow;
step 2), judging whether an ultrasonic echo signal is acquired: if yes, the acquired ultrasonic echo signals do not need to be stored, and the delay time is unchanged; otherwise, executing step 3);
step 3) defining the initial time t for starting to acquire the ultrasonic echo signalsdelay＝tdelay0，tdelay0The initial time for starting to acquire the ultrasonic echo signal under pure liquid is based on the initial time tdelay0Starting to collect ultrasonic echo signals;
step 4), judging whether an ultrasonic echo signal is acquired: if yes, the acquired ultrasonic echo does not need to be stored, and the delay time is unchanged; otherwise, starting to acquire the initial time t of the ultrasonic echo signaldelayIncreasing by taking 20 mus as a step length;
step 5) circulating the step 4) until the ultrasonic echo signals are collected, storing the collected ultrasonic echo signals, and setting time delay tdelay；
Step 6), calculating according to the collected ultrasonic echo signals to obtain uplink and downlink time difference delta t and uplink time tupTime of downlink tdown；
Step 7), obtaining the instantaneous flow q through calculation1Mixed density ρ of two-phase fluid, liquid volume fraction LVF, gas volume fraction GVF, and liquid flow rate q in gas-liquid two-phase flowlGas flow rate qgLiquid phase cumulative flow rate QlGas phase cumulative flow rate Qg。
Further, the number of points collected in step 1) is 2nStarting to time at the starting time of sending the ultrasonic excitation signal, starting to collect when the set time for starting to collect the echo signal is reached, and recording the initial time for starting to collect the echo signal as tdelayThe number of the collected points is 512, and the dynamic time delay mechanism for collecting the echo signals can reduce the time for collecting the echo signals, the consumption of a memory and the operation time of a cross-correlation algorithm under the condition of ensuring that the complete echo signals are collected.
Further, in step 2), the method for determining whether the ultrasonic echo signal is acquired is: if the maximum value of the acquired signals is larger than 2V and the position of 512 points corresponding to the maximum value is between 200 th and 300 th points, acquiring ultrasonic echo signals; otherwise, no ultrasonic echo signal is acquired.
Further, in step 3), the initial time tdelay0The calculation formula of (a) is as follows:
in the formula (1), tdelay0Is given by s, L is the vocal tract length, m, 1450 is the propagation velocity of the ultrasonic wave in water, m/s.
Further, in step 6), the calculation method of each parameter is as follows:
the uplink time tupThe calculation method of (2) is as follows: performing cross-correlation operation on the ultrasonic echo signal in the downstream direction and the stored static ultrasonic echo signal in the zero flow in the downstream direction; taking the front L points, the maximum point and the rear L points of the maximum point corresponding to the abscissa T after cross-correlation operation to form an input signal in a three-parameter fitting sinusoidal curve algorithm, wherein L is a natural number, the frequency omega of a sinusoidal curve to be fitted is the excitation frequency of an ultrasonic transducer, then obtaining the abscissa i corresponding to the maximum point of the fitted curve through the three-parameter fitting curve algorithm, and then ascending time T is obtainedupCan be calculated by the following formula:
tup＝(T-L+i)÷Fs (2)
if the dynamic wave storage and dynamic time delay mechanism is started in the measurement process, the uplink time tupThe calculation of (c) requires subtracting (t) from the formula (2)delay1-tdelay)；
The calculation method of the uplink and downlink time difference delta t comprises the following steps: performing cross-correlation operation on the ultrasonic echo signals in the downstream direction and the ultrasonic echo signals in the upstream direction; taking the front L 'point, the maximum point and the rear L' point corresponding to the maximum point after cross-correlation operation to form an input signal in a three-parameter fitting sinusoidal curve algorithm, wherein L 'is a natural number, the frequency omega of a sinusoidal curve to be fitted is the excitation frequency of an ultrasonic transducer, then obtaining the abscissa i' corresponding to the maximum point of the fitted curve through the three-parameter fitting curve algorithm, and then calculating the up-down time difference delta T through the following formula:
Δt＝(T′-L′+i′)÷Fs (3)
in equations (2) to (3), Fs is the sampling frequency of the signal;
the downlink time tdownThe calculation formula of (c) is as follows.
tdown＝tup-Δt (4)
Further, in step 7), the calculation method of each parameter is as follows:
the instantaneous flow rate q1The formula for calculating (a) is as follows,
in the formula (5), D is the diameter of the pipeline, and phi is the included angle between the uplink and downlink transducers and the axis of the pipeline;
the mixing density rho of the two-phase fluid is obtained by calculation in the combined formulas (6) and (7),
ρ＝ΔP×K2/(q1)2 (6)
in the formula (6), delta P is a differential pressure measurement value and is obtained by collecting a differential pressure signal and calibrating, and K is a differential pressure coefficient; in the formula (7), c is the outflow coefficient, β is the diameter ratio, ε is the expansion coefficient, and d is the orifice diameter of the orifice.
The liquid volume fraction LVF in the gas-liquid two-phase flow is calculated by the formula (8),
the gas volume fraction GVF is calculated by the formula (9),
GVF＝1-LVF (9)
flow rate q of liquidlThe calculation is carried out by the formula (10),
ql＝q1×LVF (10)
gas flow rate qgThe calculation is carried out by the formula (11),
qg＝q1×GVF (11)
cumulative flow Q of liquid phaselThe calculation is carried out by the formula (12),
gas phase cumulative flow rate QgThe calculation is carried out by the formula (13),
further, the ultrasonic measurement unit comprises a temperature sensor, a pressure sensor, a first ultrasonic transducer, a second ultrasonic transducer, a third ultrasonic transducer and a fourth ultrasonic transducer; the first ultrasonic transducer and the second ultrasonic transducer are positioned on the same axis and are respectively arranged on the pipe wall in an inclined and opposite manner, the third ultrasonic transducer and the fourth ultrasonic transducer are positioned on the same axis and are respectively arranged on the pipe wall in an inclined and opposite manner, and two axes of the four ultrasonic transducers are in an X shape; and the temperature sensor and the pressure sensor are respectively arranged on the front pipe wall and the rear pipe wall of the installation positions of the four ultrasonic transducers.
Furthermore, the differential pressure measurement unit comprises a differential pressure sensor and a wedge-shaped throttling device, the wedge-shaped throttling device is arranged on the inner wall of the pipeline, and two sides of the differential pressure sensor are respectively communicated with the front position and the rear position of the pipeline where the wedge-shaped throttling device is located.
Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects: the method for measuring the parameters of the gas-liquid two-phase flow in the pipeline measures the parameters of the gas-liquid two-phase flow in the pipeline by combining an ultrasonic measuring unit and a differential pressure measuring unit, and introduces a dynamic wave storage and dynamic time delay mechanism under the measurement of a two-phase medium, thereby solving the problem of incomplete acquired echo signals caused by large difference of sound wave propagation speeds of ultrasonic waves in the gas-phase medium and the liquid-phase medium in the existing sampling mechanism, and having the advantages of no radioactive pollution, reliable and stable measuring result and the like.
In addition, the ultrasonic measurement unit comprises a temperature sensor and a pressure sensor which are used for measuring real-time temperature and pressure and can also be used for temperature and pressure compensation of standard condition flow measurement.
Drawings
FIG. 1 is a flow chart of a gas-liquid two-phase flow parameter measurement method provided by the present invention;
fig. 2 is a schematic structural diagram of the gas-liquid two-phase flow meter provided by the present invention.
Wherein: 1 is a flange; 2 is a pipe section; 3 is a temperature sensor; 4 is a pressure sensor; 5 is a first ultrasonic transducer; 6 is a second ultrasonic transducer; 7 is a third ultrasonic transducer; 8 is a fourth ultrasonic transducer; 9 is a wedge-shaped throttling device; 10 is a differential pressure sensor; 11 is a header control arithmetic unit; 12 is an ultrasonic measuring unit; and 13 is a differential pressure measuring unit.
Detailed Description
The invention is described in further detail below with reference to the following figures and examples:
examples
Referring to fig. 1, the invention provides a method for measuring parameters of a gas-liquid two-phase flow, which simultaneously adopts an ultrasonic measuring unit and a differential pressure measuring unit to measure parameters of the gas-liquid two-phase flow in a pipeline, and introduces a dynamic wave storage and dynamic time delay mechanism under the measurement of a two-phase medium, and specifically comprises the following steps: taking the state when the two-phase medium is pure gas as the initial state of a dynamic wave storage and dynamic time delay mechanism, in pure gas, after an ultrasonic excitation signal is sent, carrying out time delay and then starting to collect an echo signal, and storing a static ultrasonic echo signal at zero flow; judging whether an ultrasonic echo signal is acquired or not under a two-phase medium, if the ultrasonic echo signal is acquired, not starting a dynamic wave storage and dynamic time delay mechanism, and if the ultrasonic echo signal is not acquired, starting the dynamic wave storage and dynamic time delay mechanism; and calculating according to the structural parameters, the medium parameters, the acquired ultrasonic echo signals and the differential pressure signals to obtain all parameters of the gas-liquid two-phase flow. The structural parameters refer to the general names of parameters related to the structure aspect of the detection device used in the process of calculating all parameters of the gas-liquid two-phase flow, and include parameters in a differential pressure coefficient, pipeline diameter D and other parameters; the media parameter comprises a density parameter.
Further, the gas-liquid two-phase flow parameter measuring method specifically comprises the following steps:
step 1), defining initial time t for starting to acquire ultrasonic echo signalsdelay＝tdelay1，tdelay1Initial time for starting to acquire ultrasonic echo signals under pure gas based on initial time tdelay1Starting to acquire ultrasonic echo signals, and storing static ultrasonic echo signals at zero flow; the number of the collected points is 512, the selection of 512 points is the optimal sampling point number of the invention, the sampling point number is not limited to 512 points, and other sampling points are also suitable for the invention;
step 2), judging whether an ultrasonic echo signal is acquired, wherein the specific judging method is as follows: if the maximum value of the acquired signals is larger than 2V and the position of 512 points corresponding to the maximum value is between 200 th and 300 th points, judging that the ultrasonic echo signals are acquired, wherein the acquired ultrasonic echo signals do not need to be stored, and the delay time is unchanged; otherwise, judging that the ultrasonic echo signals are not acquired, and executing the step 3);
step 3) defining the initial time t for starting to acquire the ultrasonic echo signalsdelay＝tdelay0，tdelay0The initial time for starting to acquire the ultrasonic echo signal under pure liquid is based on the initial time tdelay0Starting to collect ultrasonic echo signals;
further, tdelay0The calculation formula of (a) is as follows:
in the formula (1), tdelay0The unit of (1) is s, L is the sound channel length, the unit is m, 1450 is the propagation speed of the ultrasonic wave in water, and the unit is m/s;
step 4), judging whether an ultrasonic echo signal is acquired: if yes, the acquired ultrasonic echo does not need to be stored, and the delay time is unchanged; otherwise, starting to acquire the initial time t of the ultrasonic echo signaldelayThe step length is increased by 20 mu s, namely the initial time t for starting to acquire the ultrasonic echo signal at the current momentdelayEqual to the initial time for starting to acquire the ultrasonic echo signal at the last moment plus 20 mu s;
step 5) circulating the step 4) until the ultrasonic echo signals are collected and stored, and setting time delay tdelay；
Step 6), calculating according to the collected ultrasonic echo signals to obtain uplink and downlink time difference delta t and uplink time tupTime of downlink tdown；
Step 7), obtaining the instantaneous flow q through calculation1Mixed density ρ of two-phase fluid, liquid volume fraction LVF, gas volume fraction GVF, and liquid flow rate q in gas-liquid two-phase flowlGas flow rate qgLiquid phase cumulative flow rate QlQi, QiPhase cumulative flow rate Qg。
Further, the uplink and downlink time difference Δ t and the uplink time tupTime of downlink tdownThe calculation method of (2) is as follows:
step a), knowing that the frequency of an ultrasonic transducer is omega, the frequency is the frequency of a sine curve to be fitted, the length of an acquired signal is n, and the sampling frequency of the signal is Fs;
step b), collecting two paths of signals, namely x (n) and y (n), wherein x (n) is an ultrasonic echo signal in a downstream direction, the downstream direction can be shown in figure 2, y (n) is an ultrasonic echo signal in a countercurrent direction, and n is a signal length;
c), zero padding is carried out before signals x (N), zero padding is carried out after signals y (N), the length of the sequence after zero padding is N, the length of N needs to be 2r, r is a natural number, and the signals after zero padding are x '(N) and y' (N);
step d), Fast Fourier Transform (FFT) is respectively carried out on the x '(n) and the y' (n) to obtain signals x (k) and y (k);
step e) determining the conjugate of x (k) as x*(k) X is to be*(k) Multiplying by y (k) to obtain a signal Rxy(k)；
Step f) for Rxy(k) Inverse Fourier transform (IFFT) is carried out to obtain a cross-correlation signal Rxy(τ)；
Step g) for Rxy(tau) performing a peak search to find the cross-correlation signal Rxy(τ) the abscissa corresponding to the maximum point is denoted as T;
step h), taking the cross-correlation signal Rxy(τ) maximum point (T, R)xy(T)) the ordinate of the first L points, the maximum point and the last L points form a signal y,
step i), constructing a matrix M,
step j), calculating
Step k), fitting a sine curve expression as follows:
wherein
Step l), let ω i + θ be 0, and the abscissa corresponding to the maximum point of the fitted sinusoid is i, then
Step m), determining the uplink and downlink time difference delta T ═ T-L + i ÷ Fs;
step n), collecting two paths of signals, namely x (n) and y (n), wherein x (n) is an ultrasonic echo signal in the downstream direction, y (n) is a stored static ultrasonic echo signal in the downstream direction under zero flow, and n is the signal length;
step o), repeating steps c) to l), uplink time tup(T-L + i) ÷ Fs; the uplink time t is set due to the dynamic wave storage and the dynamic start of the collection of the echo timeupThe calculation requires subtraction of (t)delay1-tdelay) Wherein, tdelay1Initial time t for starting to collect ultrasonic echo signal under pure gasdelayTime delay of the ultrasonic echo signal acquired in the step 5);
step p), down time tdown＝tup-Δt。
Further, the calculation method of each parameter in step 7) is as follows:
calculating formula according to flow
Obtaining a flow value to be measured, wherein D is the diameter of the pipeline, and phi is the included angle between the upstream transducer and the downstream transducer and the axis of the pipeline;
calculating by combining the formulas (6) and (7) to obtain the mixed density rho of the two-phase fluid,
ρ＝ΔP×K2/(q1)2 (6)
in the formula (6), delta P is a differential pressure measurement value and is obtained by collecting a differential pressure signal and calibrating, and K is a differential pressure coefficient; in the formula (7), c is an outflow coefficient, beta is a diameter ratio, epsilon is an expansion coefficient, and d is the aperture of the throttling element;
thirdly, the liquid volume fraction LVF and the gas volume fraction GVF in the gas-liquid two-phase flow are respectively calculated by combining the formulas (8) and (9),
GVF＝1-LVF (9)
fourthly, the liquid flow q in the gas-liquid two-phase flow is calculated by combining the formula (10)l，
ql＝q1×LVF (10)
Calculating to obtain the gas flow q in the gas-liquid two-phase flow by combining the formula (11)g，
qg＝q1×GVF (11)
Sixthly, the liquid phase cumulative flow Q is obtained by combining the formula (12)l，
Seventhly, the gas phase accumulated flow Q is obtained by calculation according to the formula (13)g，
Further, the density of the gas is obtained by a densitometer algorithm in the national standard GB/T11062-2014, and the density rho of the liquidQi (Qi)Is based on the collection and measurement of the liquid on site.
The device based on the gas-liquid two-phase flow parameter measuring method has the following specific structure and working process: the device is shown in fig. 2 and comprises a gauge outfit control operation unit 11, a flange 1, a pipe section 2, a temperature sensor 3, a pressure sensor 4, a first ultrasonic transducer 5, a second ultrasonic transducer 6, a third ultrasonic transducer 7 and a fourth ultrasonic transducer 8, wherein the four ultrasonic transducers, the temperature sensor 3 and the pressure sensor 4 form an ultrasonic measurement unit 12, and a wedge-shaped throttling device 9 and a differential pressure sensor 10 form a differential pressure measurement unit 13.
Furthermore, the first ultrasonic transducer 5 and the second ultrasonic transducer 6 are positioned on the same axis and are respectively arranged on the pipe wall in an inclined manner, the third ultrasonic transducer 7 and the fourth ultrasonic transducer 8 are positioned on the same axis and are respectively arranged on the pipe wall in an inclined manner, and two axes of the four ultrasonic transducers are in an X shape; the temperature sensor 3 and the pressure sensor 4 are respectively arranged on the front pipe wall and the rear pipe wall of the installation positions of the four ultrasonic transducers, and temperature and pressure measurement values are obtained through signal conditioning and acquisition calculation and are used for temperature and pressure compensation of standard condition flow measurement; the ultrasonic measurement unit 12 controls four ultrasonic transducers through the meter head control operation unit 11, for a total of four modes: in the first mode, when the first ultrasonic transducer 5 sends a signal, the second ultrasonic transducer 6 receives the signal; in the second mode, when the second ultrasonic transducer 6 sends a signal, the first ultrasonic transducer 5 receives the signal; in the third mode, the third ultrasonic transducer 7 sends signals, and the fourth ultrasonic transducer 8 receives signals; in the fourth mode, the fourth ultrasonic transducer 8 sends a signal, and the third ultrasonic transducer 7 receives the signal.
Further, the differential pressure measurement unit 13 includes a throttling device and a differential pressure sensor 10, the throttling device is a wedge-shaped throttling device 9, the throttling device in the present invention is not limited to the wedge-shaped throttling device 9, other throttling devices also accord with the working principle of the present invention, preferably, the wedge-shaped throttling device 9 is selected, the wedge-shaped throttling device 9 is arranged on the inner wall of the pipeline, two sides of the differential pressure sensor 10 are respectively communicated with the front and rear positions of the pipeline where the wedge-shaped throttling device 9 is located, and the differential pressure sensor 10 is used for measuring differential pressure signals at the front and rear ends of the throttling element.
The meter head control operation unit 11 performs time-sharing acquisition on the ultrasonic echo signals in four modes through one ADC acquisition module, the acquisition mechanism of the echo signals is to start timing at the starting time of sending the ultrasonic excitation signal and start acquisition when the set time for starting to acquire the echo signals is reached, and the time for starting to acquire the echo signals is recorded as tdelayThe number of the collection points is 512. The signal acquisition mechanism can reduce the time for acquiring the echo signals, reduce the consumption of the memory and the operation time of the cross-correlation algorithm under the condition of ensuring that the complete echo signals are acquired.
Further, the meter head control operation unit 11 includes the implementation of the mechanism and algorithm operation used in the working process of the ultrasonic measurement unit 12 and the differential pressure measurement unit 13, and also integrates the functions of menu, communication, pulse and 4-20mA output.
In conclusion, the method for measuring the gas-liquid two-phase flow parameters adds a dynamic wave storage and dynamic time delay mechanism under the condition of measuring a two-phase medium, and can solve the problem that the collected echo signals are incomplete due to the fact that the sound wave propagation speeds of ultrasonic waves in a gas-phase medium and a liquid-phase medium are greatly different in the existing collection mechanism. The flowmeter based on the gas-liquid two-phase flow parameter measuring method combines ultrasonic measurement and differential pressure measurement, and is matched with a meter head control operation unit 11 with various operation mechanisms and algorithms to form an instrument which has the advantages of simple structure, small volume, low cost, no radioactive pollution and reliable and stable measurement, and can be used for on-line monitoring of two-phase parameters of wellhead gas production and wellhead natural gas and also can be used for parameter measurement under other gas-liquid two-phase media.
The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention.
It is to be understood that the present invention is not limited to what has been described above, and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.
Claims (10)
1. A gas-liquid two-phase flow parameter measuring method is characterized in that an ultrasonic measuring unit (12) and a differential pressure measuring unit (13) are adopted to measure parameters of gas-liquid two-phase flow in a pipeline, and a dynamic wave storage and dynamic time delay mechanism is introduced under the measurement of a two-phase medium, and the method specifically comprises the following steps: taking the state when the two-phase medium is pure gas as the initial state of a dynamic wave storage and dynamic time delay mechanism, in pure gas, after an ultrasonic excitation signal is sent, carrying out time delay and then starting to collect an echo signal, and storing a static ultrasonic echo signal at zero flow; judging whether an ultrasonic echo signal is acquired or not under a two-phase medium, if the ultrasonic echo signal is acquired, not starting a dynamic wave storage and dynamic time delay mechanism, and if the ultrasonic echo signal is not acquired, starting the dynamic wave storage and dynamic time delay mechanism; and calculating according to the structural parameters, the medium parameters, the acquired ultrasonic echo signals and the differential pressure signals to obtain all parameters of the gas-liquid two-phase flow.
2. The gas-liquid two-phase flow parameter measuring method according to claim 1, comprising the steps of:
step 1), defining delay time t for starting to acquire ultrasonic echo signalsdelay＝tdelay1，tdelay1Initial time to start acquiring ultrasonic echo signals for pure gas based on the initial time tdelay1Starting to acquire ultrasonic echo signals, and storing static ultrasonic echo signals at zero flow;
step 2), judging whether an ultrasonic echo signal is acquired: if yes, the acquired ultrasonic echo signals do not need to be stored, and the delay time is unchanged; otherwise, executing step 3);
step 3) defining the delay time t for starting to acquire the ultrasonic echo signaldelay＝tdelay0，tdelay0The initial time for starting to acquire the ultrasonic echo signal under pure liquid is based on the initial time tdelay0Starting to collect ultrasonic echo signals;
step 4), judging whether an ultrasonic echo signal is acquired: if yes, the acquired ultrasonic echo does not need to be stored, and the delay time is unchanged; otherwise, starting to acquire the initial time t of the ultrasonic echo signaldelayIncreasing by taking 20 mus as a step length;
step 5) circulating the step 4) until the ultrasonic echo signals are collected, storing the collected ultrasonic echo signals, and setting time delay tdelay；
Step 6), calculating according to the collected ultrasonic echo signals to obtain uplink and downlink time difference delta t and uplink time tupTime of downlink tdown；
Step 7), obtaining the instantaneous flow q through calculation1Mixed density ρ of two-phase fluid, liquid volume fraction LVF, gas volume fraction GVF, and liquid flow rate q in gas-liquid two-phase flowlGas flow rate qgLiquid phase cumulative flow rate QlGas phase cumulative flow rate Qg。
3. The gas-liquid two-phase flow parameter measurement method according to claim 2, wherein the number of points collected in step 1) is 2nAnd (4) respectively.
4. The method according to claim 3, wherein the number of points collected in step 1) is 512.
5. The method for measuring parameters of a gas-liquid two-phase flow according to claim 4, wherein the method for determining whether the ultrasonic echo signal is collected in step 2) comprises: if the maximum value of the acquired signals is larger than 2V and the position of 512 points corresponding to the maximum value is between 200 th and 300 th points, acquiring ultrasonic echo signals; otherwise, no ultrasonic echo signal is acquired.
6. The gas-liquid two-phase flow parameter measurement method according to claim 2, wherein in step 3), the initial time t isdelay0The calculation formula of (a) is as follows:
in the formula (1), tdelay0Is given by s, L is the vocal tract length, m, 1450 is the propagation velocity of the ultrasonic wave in water, m/s.
7. The method for measuring parameters of a gas-liquid two-phase flow according to claim 2, wherein in step 6), the calculation method of each parameter is as follows:
the uplink time tupThe calculation method of (2) is as follows: performing cross-correlation operation on the ultrasonic echo signal in the downstream direction and the stored static ultrasonic echo signal in the zero flow in the downstream direction; taking the front L points, the maximum point and the rear L points of the maximum point corresponding to the abscissa T after cross-correlation operation to form an input signal in a three-parameter fitting sinusoidal curve algorithm, wherein L is a natural number, the frequency omega of a sinusoidal curve to be fitted is the excitation frequency of an ultrasonic transducer, then obtaining the abscissa i corresponding to the maximum point of the fitted curve through the three-parameter fitting curve algorithm, and then ascending time T is obtainedupCan be calculated by the following formula:
tup＝(T-L+i)÷Fs (2)
if the dynamic wave storage and dynamic time delay mechanism is started in the measurement process, the uplink time tupThe calculation of (c) requires subtracting (t) from the formula (2)delay1-tdelay)；
The calculation method of the uplink and downlink time difference delta t comprises the following steps: performing cross-correlation operation on the ultrasonic echo signals in the downstream direction and the ultrasonic echo signals in the upstream direction; taking the front L 'point, the maximum point and the rear L' point corresponding to the maximum point after cross-correlation operation to form an input signal in a three-parameter fitting sinusoidal curve algorithm, wherein L 'is a natural number, the frequency omega of a sinusoidal curve to be fitted is the excitation frequency of an ultrasonic transducer, then obtaining the abscissa i' corresponding to the maximum point of the fitted curve through the three-parameter fitting curve algorithm, and then calculating the up-down time difference delta T through the following formula:
Δt＝(T′-L′+i′)÷Fs (3)
in equations (2) to (3), Fs is the sampling frequency of the signal;
the downlink time tdownThe calculation formula of (c) is as follows.
tdown＝tup-Δt (4)
8. The method for measuring parameters of a gas-liquid two-phase flow according to claim 2, wherein in step 7), the calculation method of each parameter is as follows:
the instantaneous flow rate q1The formula for calculating (a) is as follows,
in the formula (5), D is the diameter of the pipeline, and phi is the included angle between the uplink and downlink transducers and the axis of the pipeline;
the mixing density rho of the two-phase fluid is obtained by calculation in the combined formulas (6) and (7),
ρ＝ΔP×K2/(q1)2 (6)
in the formula (6), delta P is a differential pressure measurement value and is obtained by collecting a differential pressure signal and calibrating, and K is a differential pressure coefficient; in the formula (7), c is the outflow coefficient, β is the diameter ratio, ε is the expansion coefficient, and d is the orifice diameter of the orifice.
The liquid volume fraction LVF in the gas-liquid two-phase flow is calculated by the formula (8),
in the formula (8), ρQi (Qi)Is the density of the gas in a two-phase gas-liquid flow, the pQi (Qi)Can be obtained according to a density calculation method in the national standard GB/T11062-2014; rhoLiquid for treating urinary tract infectionThe density of liquid in the gas-liquid two-phase flow can be set by sampling the actual liquid on the application site;
the gas volume fraction GVF is calculated by the formula (9),
GVF＝1-LVF (9)
flow rate q of liquidlThe calculation is carried out by the formula (10),
ql＝q1×LVF (10)
gas flow rate qgThe calculation is carried out by the formula (11),
qg＝q1×GVF (11)
cumulative flow Q of liquid phaselThe calculation is carried out by the formula (12),
gas phase cumulative flow rate QgThe calculation is carried out by the formula (13),
9. the gas-liquid two-phase flow parameter measuring method according to any one of claims 1 to 8, wherein the ultrasonic measuring unit (12) comprises a temperature sensor (3), a pressure sensor (4), a first ultrasonic transducer (5), a second ultrasonic transducer (6), a third ultrasonic transducer (7) and a fourth ultrasonic transducer (8); the first ultrasonic transducer (5) and the second ultrasonic transducer (6) are positioned on the same axis and are respectively arranged on the pipe wall in an inclined and opposite mode, the third ultrasonic transducer (7) and the fourth ultrasonic transducer (8) are positioned on the same axis and are respectively arranged on the pipe wall in an inclined and opposite mode, and two axes of the four ultrasonic transducers are in an X shape; and the temperature sensor (3) and the pressure sensor (4) are respectively arranged on the front pipe wall and the rear pipe wall of the four ultrasonic transducer mounting positions.
10. The gas-liquid two-phase flow parameter measurement method according to any one of claims 1-8, wherein the differential pressure measurement unit (13) comprises a differential pressure sensor (10) and a wedge-shaped throttling device (9), the wedge-shaped throttling device (9) is arranged on the inner wall of the pipeline, and two sides of the differential pressure sensor (10) are respectively communicated with the front position and the rear position of the pipeline where the wedge-shaped throttling device (9) is located.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113933385A (en) * | 2021-10-08 | 2022-01-14 | 哈尔滨工程大学 | Oil and gas share measuring device and method based on ultrasonic fusion technology |
| CN114812707A (en) * | 2022-05-16 | 2022-07-29 | 瑞纳智能设备股份有限公司 | Metering method of ultrasonic meter |
| CN115825222A (en) * | 2022-12-27 | 2023-03-21 | 天津大学 | Method for identifying slug flow structure based on ultrasonic technology |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1113247A1 (en) * | 1999-12-28 | 2001-07-04 | Gaz De France | Method and device for measuring a fluid flow in a pipeline |
| JP2008249400A (en) * | 2007-03-29 | 2008-10-16 | Tokyo Electric Power Co Inc:The | Flow measuring device, flow measuring method, and computer program |
| CN102297712A (en) * | 2011-07-12 | 2011-12-28 | 北京理工大学 | Method for measuring propagation time of ultrasonic echo |
| CN106871980A (en) * | 2017-02-13 | 2017-06-20 | 合肥工业大学 | The excitation of gas ultrasonic flowmeter batch (-type) and signal processing method and system based on adjacent peak maximum difference |
| US20180010943A1 (en) * | 2015-03-24 | 2018-01-11 | Hefei University Of Technology | Ultrasonic gas flow meter based on fpga and dsp |
| CN107860430A (en) * | 2017-10-19 | 2018-03-30 | 西安安森智能仪器股份有限公司 | A kind of ultrasonic gas flowmeter measurement method for time difference based on time difference method |
| CN109506729A (en) * | 2018-12-27 | 2019-03-22 | 西安安森智能仪器股份有限公司 | A kind of biphase gas and liquid flow parameter online test method and device |
| CN109506727A (en) * | 2018-12-24 | 2019-03-22 | 西安安森智能仪器股份有限公司 | A kind of ultrasonic flow measuring method and low-consumption ultrasonic flow measurement meter |
-
2019
- 2019-09-09 CN CN201910849490.5A patent/CN110631958B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1113247A1 (en) * | 1999-12-28 | 2001-07-04 | Gaz De France | Method and device for measuring a fluid flow in a pipeline |
| JP2008249400A (en) * | 2007-03-29 | 2008-10-16 | Tokyo Electric Power Co Inc:The | Flow measuring device, flow measuring method, and computer program |
| CN102297712A (en) * | 2011-07-12 | 2011-12-28 | 北京理工大学 | Method for measuring propagation time of ultrasonic echo |
| US20180010943A1 (en) * | 2015-03-24 | 2018-01-11 | Hefei University Of Technology | Ultrasonic gas flow meter based on fpga and dsp |
| CN106871980A (en) * | 2017-02-13 | 2017-06-20 | 合肥工业大学 | The excitation of gas ultrasonic flowmeter batch (-type) and signal processing method and system based on adjacent peak maximum difference |
| CN107860430A (en) * | 2017-10-19 | 2018-03-30 | 西安安森智能仪器股份有限公司 | A kind of ultrasonic gas flowmeter measurement method for time difference based on time difference method |
| CN109506727A (en) * | 2018-12-24 | 2019-03-22 | 西安安森智能仪器股份有限公司 | A kind of ultrasonic flow measuring method and low-consumption ultrasonic flow measurement meter |
| CN109506729A (en) * | 2018-12-27 | 2019-03-22 | 西安安森智能仪器股份有限公司 | A kind of biphase gas and liquid flow parameter online test method and device |
Non-Patent Citations (1)
| Title |
|---|
| 陈洁等: "基于双阈值比较法超声波流量计信号处理", 《电子测量与仪器学报》, vol. 27, no. 11, 15 November 2013 (2013-11-15), pages 1024 - 1032 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113933385A (en) * | 2021-10-08 | 2022-01-14 | 哈尔滨工程大学 | Oil and gas share measuring device and method based on ultrasonic fusion technology |
| CN114812707A (en) * | 2022-05-16 | 2022-07-29 | 瑞纳智能设备股份有限公司 | Metering method of ultrasonic meter |
| CN114812707B (en) * | 2022-05-16 | 2023-03-14 | 瑞纳智能设备股份有限公司 | Metering method of ultrasonic meter |
| CN115825222A (en) * | 2022-12-27 | 2023-03-21 | 天津大学 | Method for identifying slug flow structure based on ultrasonic technology |
| CN115825222B (en) * | 2022-12-27 | 2024-06-04 | 天津大学 | Method for identifying slug flow structure based on ultrasonic technology |
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