In the development process of oil gas field, the production fluid composition in the oil gas well mainly comprises oil, gas, water three-phase.At present; Utilize complex structure, bulky aboveground heterogeneous separate measurement technology; The flow velocity of metering multiphase flow, production process parameters such as discrete phase density, volume flow and mass flow; Especially wherein rate of flow of fluid and total volumetric flow rate are significant to metering, management and the control etc. of manufacturing process.But; Along with shift to areas such as the abominable polar regions of desert, ocean and ambient conditions gradually in the development zone of petroleum industry; Incidently be; The restriction of aspect such as little such as the platform area, that installing space is limited, cost of investment is low makes traditional heterogeneous separate measurement lose the advantage of self.
Big to viscosity of crude, be prone to absorption, impurity content is high and contains characteristic such as anti-coagulants; And the problem that aspect design, installation, operation, maintenance and maintenance, exists of mining system, the higher measuring apparatus of current frequency of utilization comprises: volumetric flowmeter, turbine flowmeter and electromagnetic flowmeter etc.Wherein volumetric flowmeter is the rotation through inner rotator, and the number of times that detected fluid is discharged through metrology room measures as foundation.Owing to there are mechanical components such as mechanical rotor, axle, bearing and gear, the gauge table easy abrasion causes maintenance bigger, and particularly for impure more slurry oil, the screen pack easy blocking causes gauge table accurately to measure.Although that turbine flowmeter has is simple in structure, the pressure loss is little, advantages such as good linear relationship are arranged between secondary speed and the flow; But the instrumental constant of turbine flowmeter is subject to the influence of long-term work and maintenance; Make certainty of measurement reduce, and the easy problem that can't be measured by the impurity obstruction of the same existence of turbine flowmeter.Electromagnetic flowmeter can only be measured the liquid of conduction, and the electric conductivity of the anti-coagulants in the adding crude oil is more weak or do not have electric conductivity, therefore can't use.
Summary of the invention
To the problems referred to above, the purpose of the utility model provides a kind of convenient, fast, and the underground ultrasonic ripple doppler flow measuring device that can measure flow exactly.
For realizing above-mentioned purpose, the utility model is taked following technical scheme: a kind of underground ultrasonic ripple doppler flow measuring device, and it is characterized in that: it comprises ultrasonic transmitting element, ultrasonic wave receiving element, signal processing unit and data storage cell; Said ultrasonic transmitting element comprises a driver element and a transmitting probe; Said ultrasonic wave receiving element is a reflection probe; Said transmitting probe and reflection probe are symmetricly set on the oil-pipe external wall; Said transmitting probe and reflection probe comprise a shell respectively, are tiltedly installed with a supporting clapboard respectively in the two said shells, are pasted with a piezoelectric element respectively on the two said supporting clapboards; Said signal processing unit comprises analogy signal processing unit and data processing unit, and said analogy signal processing unit comprises bandpass filtering and demodulator amplifier, low pass filter, signal amplifier and photoelectrical coupler; Said bandpass filtering and demodulator amplifier carry out filtering, amplification to reflection supersonic wave; And demodulate reflection ultrasonic signal and the pumping signal that presets between a frequency offset signal; Said frequency offset signal carries out that high-frequency noise filtering, said input signal amplifier are amplified and said photoelectrical coupler carries out importing said data processing unit after electricity-light-electricity changes through said low pass filter successively; Said data processing unit comprises central processing unit, peripheral circuit, current/voltage transformation device and peripheral interface; Said central processing unit comprises A/D sampling module, timing interrupt service routine, data buffer area and CPU; Said A/D sampling module is sampled to frequency offset signal and is converted data signal to; Through regularly interrupt service routine and data buffer zone get into said CPU; Preset the design formulas of instrument parameter and conduit volume flow in the said CPU; The instantaneous velocity of the fluid multiphase flow that calculates, integrated flow class data volume are imported in the said data storage cell.
The utility model is owing to take above technical scheme; It has the following advantages: 1, the utility model is owing to adopt supersonic Doppler flow measurement mode that the down-hole multiphase flow is measured; Therefore compare with the flow meter of routine metering oilwell produced fluid amount, not only the little pipeline drift diameter that do not take of volume, convection cell generation additional drag; And precision is high, is a kind of desirable energy-saving flow meter.2, the utility model measurement mechanism does not receive temperature, pressure, the viscosity of tested oil body, the influence of density, has time stability, temperature stability and corrosion resistance preferably, but the flow monitoring of prolonged application multiphase flow in the down-hole.3, the transducer of the utility model device unlikely change that causes detected fluid flow field form of sound wave of sending; Enough intensity and stability are arranged again simultaneously; Make the acoustic signal that is loaded with flow information that receives that maximum signal to noise ratio arranged; Can obtain maximum Doppler frequency shift, with convenient instantaneous velocity, the integrated flux that calculates in the oil pipe.4, the utility model rating of set is little, and volume is light and handy, and resolution ratio is high, and is fast to the change in flow response, if the good reproducibility of instrument when test condition is constant.5, the utility model is owing to adopt the down-hole mounting means; Therefore can obtain heterogeneous data volume in real time, do not measured time restriction, reduce the production loss that causes because of measurement effectively; And then reached the expense of saving oil field investment, operation and safeguarding, be convenient to the purpose of field management.The utility model is applicable to the real-time measurement of producing well down-hole multiphase flow rates in the oil-gas field development.
The specific embodiment
Below in conjunction with accompanying drawing and embodiment the utility model is carried out detailed description.
As shown in Figure 1, the measurement mechanism of the utility model comprises a ultrasonic transmitting element 1, a ultrasonic wave receiving element 2, a signal processing unit 3 and a data storage cell 4.
Like Fig. 1, shown in Figure 2, the ultrasonic transmitting element 1 of the utility model is flowing fluid emission ultrasonic wave in oil pipe 5, and the flow direction of launching fluid in hyperacoustic beam planes and the oil pipe 5 is an angle.Ultrasound beamformer can produce reflection supersonic wave after being reflected by the suspended particles of motion in the oil pipe 5, and reflection supersonic wave is received and input signal processing units 3 by ultrasonic wave receiving element 2.According to Doppler effect, reflection supersonic wave will certainly produce a frequency departure with respect to the emission ultrasonic wave, and signal processing unit 3 can obtain an amounts of frequency offset according to the frequency departure between emission ultrasonic wave and the reflection supersonic wave.According to the angle that the flow direction was of fluid in amounts of frequency offset and emission ultrasound beamformer and the oil pipe 5, can calculate the needed data volumes such as instantaneous velocity, integrated flow of multiphase flow in the oil pipe 5, and store in the data storage cell 4.After measure finishing, use desktop computer, notebook computer or dedicated ground appearance, can needed data such as being stored in instantaneous velocity in the data storage cell 4, integrated flow be carried out playback and printing.
Like Fig. 3, shown in Figure 4, the utility model ultrasonic transmitting element 1 comprises a driver element 6 and a transmitting probe 7, and transmitting probe comprises a shell 71, and shell 71 tilt are provided with a supporting clapboard 72, are bonded with a piezoelectric element 73 on the surface of supporting clapboard 72.Piezoelectric element 73 can adopt ceramic wafers, also can adopt PZT (piezoelectric transducer) wafer etc.Angular range in supporting clapboard 72 and the oil pipe 5 between the flow direction of fluid is 0～90 °, is preferably 45 °.Support dividing plate 72 is divided into large and small two spaces with shell 71; Piezoelectric element 73 is positioned at less space; Bigger space is to be filled with ultrasonic wave sound absorption material 74 in the backing; Such as the sound absorption material of high impedances such as silica gel, high decay, with the ultrasonic wave of absorption pressure electric device back side radiation and be converted into heat energy, and isolated outside noise disturbs.Driver element 6 is the pumping signal of 150KHZ～1MHZ to transmitting probe 7 transmit frequency ranges, wherein is the excitation signal energizes best results of 650KHZ with the frequency.Driver element 6 can adopt an independent exciting circuit that is provided with, and also can adopt the device with identical function well known in the art.
The utility model ultrasonic wave receiving element 2 is a receiving transducer 8; The structure of shell, supporting clapboard 82 and piezoelectric element 83 is identical with the structure of transmitting probe 7 in the receiving transducer 8; Wherein supporting clapboard 72 and the piezoelectric element 73 in direction and the transmitting probe 7 of being provided with of supporting clapboard 82 and piezoelectric element 83 is and is symmetrical set; The ultrasonic signal that produces after piezoelectric element 73 excited target on the transmitting probe 7 like this; Can inject in the fluid in the oil pipe 5 along certain angle, reflex on the piezoelectric element 83 of reflection probe 8 through the suspended particles that move in the oil pipe, reflection probe 8 is sent reflection ultrasonic signal into signal processing unit 3 again.For the shell 71 of transmitting probe 7 and the shell 81 of receiving transducer 8 are installed on oil pipe 5 outer walls, symmetry offers two draw-in grooves 9 that are complementary with shell 71,81 on oil pipe 5 outer walls, and transmitting probe 7 is separately fixed in the draw-in groove 9 with receiving transducer 8.
As shown in Figure 3, the signal processing unit 3 of the utility model comprises an analogy signal processing unit 10 and a data processing unit 11.Analogy signal processing unit 10 in the signal processing unit 3 comprises a bandpass filtering and demodulator amplifier 12, a low pass filter 13, a signal amplifier 14 and a photoelectrical coupler 15.Preset the exciting signal frequency that driver element 6 is launched in bandpass filtering and the demodulator amplifier 12; The reflection supersonic wave of 12 pairs of ultrasonic wave receiving elements of bandpass filtering and demodulator amplifier, 2 outputs; Carry out filtering, amplification and demodulation process; Frequency offset signal between the pumping signal that the driver element 6 that demodulates reflection ultrasonic signal and preset is launched, and with the frequency offset signal input low pass filter 13 that obtains; After low pass filter 13 carried out high-frequency noise filtering processing with frequency offset signal, input signal amplifier 14 carried out signal and amplifies, and the frequency offset signal after being exaggerated is admitted to photoelectrical coupler 15; In photoelectrical coupler 15, will carry out electricity-light-electricity conversion to the frequency offset signal after amplifying, isolation input, output frequency offset signal, and will isolate back output frequency offset signal and carry out linearity amplification back output, to improve the anti-interference of frequency offset signal.
Like Fig. 3, shown in Figure 4, the data processing unit 11 in the utility model signal processing unit 3 comprises central processing unit 16, peripheral circuit 17, current/voltage transformation device 18 and peripheral interface 19.Central processing unit 17 comprises an A/D sampling module 20, regularly interrupt service routine 21, a data buffer area 22 and a CPU (central processing unit).The frequency offset signal of photoelectrical coupler 15 outputs is sampled in 20 pairs of analogy signal processing units 10 of A/D sampling module, and converts the frequency offset signal that collects to data signal, incoming timing interrupt service routine 21.Regularly interrupt service routine 21 is sent into CPU with the frequency offset signal of input through data buffer zone 22.Preset the design formulas of the volume flow of instrument parameter and pipeline 5 among the CPU, the instrument parameter specifically comprises angle theta and hyperacoustic tranmitting frequency f between cross-sectional area s, ultrasonic beam and the direction of flow of pipeline 5
1CPU is according to the frequency offset signal that receives, in conjunction with the design formulas of the volume flow of instrument parameter that presets and pipeline 5, calculates the flow of fluid in the pipeline 5; Be the needed data volumes such as instantaneous velocity, integrated flow of multiphase flow, store data storage cell 4 storages into.Also can the data volume that obtain be flowed to current/voltage transformation device 18 through peripheral circuit 17, current/voltage transformation device 18 converts the voltage signal of input the normalized current signal of 4～20mA to, in order to transfer of data, collection, storage.
The principle that above-mentioned CPU calculates the volume flow of fluid in the pipeline 5 is following: according to Doppler's flow measurement principle, when the transmitting probe 7 of ultrasonic Doppler flowmeter is f with certain angle to oil pipe 5 ducted fluid tranmitting frequencies
1The continuous ultrasound ripple time, establishing the ultrasonic frequency of receiving is f
2, the spread speed of ultrasonic wave in detected fluid is c, and with speed u motion, angle is θ between ultrasonic beam and the direction of flow with fluid for oil pipe 5 ducted particles or bubble, and then Doppler frequency shift Δ f is:
Oil pipe 5 ducted flow rate of fluid are:
If the cross-sectional area of oil pipe 5 pipelines is s, then the volume flow Q of fluid is in the pipeline 5:
Can know by (3) formula; The spread speed of ultrasonic wave in detected fluid is angle theta, hyperacoustic tranmitting frequency f1 between cross-sectional area s, ultrasonic beam and the direction of flow of c, pipeline 5; Measure Doppler frequency shift Δ f, just can calculate fluid volume flow Q.
As shown in Figure 5, the peripheral interface 19 in the utility model signal processing unit 3 comprises a jtag interface and a RS485 interface.Jtag interface is 4 lines, is respectively model selection TMS, clock TCK, data input TDI, data output TDO, is mainly used in central processing unit 16 close betas and system is carried out emulation, debugging.
If the peripheral circuit 17 in the above-mentioned signal processing unit 3 is only as transmission circuit; It can adopt custom circuit; If except that transmission, need the change curve of real-time monitored data volume, can pass through peripheral circuit D/A converter, external RAM and display and realize.Wherein D/A converter receives the needed data volumes such as instantaneous velocity, integrated flow of CPU multiphase flow; And the data signal after will handling converts analog signal to; If data volume is kept in through RAM more greatly, the curve that terminal display display simulation signal forms.
In the foregoing description, " electricity-light-electricity conversion " refers to: being media with light is coupled to the photoelectrical coupler 15 of output to input end signal, realizes the signal of telecommunication-electro-optical signal conversion.
Among above-mentioned each embodiment, bandpass filtering and demodulator amplifier 12 can adopt narrow bend ceramic filter; Low pass filter 13 can adopt low pass filter TLC14; Signal amplifier 14 can adopt signal amplifier AD623; Photoelectrical coupler 15 can adopt Darlington type photo-coupler (like 4N30); It is the chip of TMS320F28335 that central processing unit 16 can adopt model; Current/voltage transformation device 18 can adopt the AD694 chip, and D/A converter can be 12 D/A converter DAC7625 able to programme.But all be not limited thereto.
Above-mentioned each embodiment only is used to explain the utility model; Wherein the structure of each parts, connected mode etc. all can change to some extent; Every equivalents of on the basis of the utility model technical scheme, carrying out and improvement all should not got rid of outside the protection domain of the utility model.