A wide range ratio ultrasonic flow rate testing system and testing method

Abstract

The present invention discloses a wide range ratio ultrasonic flow test system and test method. The test system includes an underground ultrasonic signal transceiver and a ground control terminal; the ultrasonic signal transceiver includes a test flow guide tube, and first and second ultrasonic transducers arranged at a certain axial distance on the test flow guide tube; the control terminal is used to determine the forward and reverse flow time difference based on the first echo signal collected by the first ultrasonic transducer and the second echo signal collected by the second ultrasonic transducer in the same test cycle, and judge whether the excitation signal period of the first ultrasonic transducer and the second ultrasonic transducer is greater than the forward and reverse flow time difference. If not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference. The system can meet the needs of a large span flow test range by adjusting the excitation frequency of the ultrasonic transducer while keeping the structural dimensions of the test flow guide tube unchanged, greatly expanding the range ratio of the flow test.

Description

Technical Field

[0001] The invention relates to the technical field of ultrasonic flow measurement, and in particular to a wide range ratio ultrasonic flow test system and test method. Background Art

[0002] Ultrasonic time difference method (or phase difference method) flow detection technology has been widely used in various fields due to its high test accuracy and strong adaptability. At present, the range ratio of ultrasonic time difference method flow test equipment is usually no more than 500:1. Large-span flow test usually requires the selection of large-caliber (flow channel) instruments, but the small flow test accuracy is very poor or even cannot be tested; small-caliber instruments are selected for small flow tests, and large flows are beyond the test range. The same caliber structure size is difficult to meet the needs of large-span flow test range (large range ratio). Summary of the invention

[0003] In order to at least partially solve the technical problems existing in the prior art, the inventors have made the present invention, and through specific implementation methods, provide a wide range ratio ultrasonic flow testing system and testing method, which can meet the needs of a large span flow testing range without changing the structural dimensions (especially the size of the flow channel), thereby greatly expanding the range ratio of the flow test.

[0004] In a first aspect, an embodiment of the present invention provides a wide range ratio ultrasonic flow rate testing system, including a downhole ultrasonic signal transceiver and a ground control terminal;

[0005] The ultrasonic signal transceiver comprises a test flow guide tube, and a first ultrasonic transducer and a second ultrasonic transducer arranged on the test flow guide tube at a certain axial distance;

[0006] The control terminal is used to determine the forward and reverse flow time difference based on the first echo signal collected by the first ultrasonic transducer and the second echo signal collected by the second ultrasonic transducer in the same test cycle, and judge whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference; if not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference.

[0007] Optionally, the control terminal determines whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, and is used to:

[0008] Determine an excitation signal period according to the excitation frequency of the first ultrasonic transducer, and judge whether the excitation signal period is greater than the forward and reverse flow time difference;

[0009] The excitation signal period is determined according to the excitation frequency of the second ultrasonic transducer, and it is determined whether the excitation signal period is greater than the forward and reverse flow time difference.

[0010] Optionally, the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer are consistent, and the control terminal determines whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, for:

[0011] The excitation signal period is determined according to the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer, and it is judged whether the excitation signal period is greater than the forward and reverse flow time difference.

[0012] Optionally, the control terminal determines whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, and if not, adjusts the excitation frequency of the corresponding ultrasonic transducer so that the excitation signal period is greater than the forward and reverse flow time difference, for:

[0013] Determine whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, and whether the absolute difference between the excitation signal half period and the forward and reverse flow time difference is both less than a set time difference threshold;

[0014] If not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference, and the absolute difference between the excitation signal half period and the forward and reverse flow time difference is less than the time difference threshold.

[0015] Optionally, the ultrasonic signal transceiver further includes a third ultrasonic transducer disposed on the test flow guide tube, wherein the third ultrasonic transducer is axially symmetrically disposed with respect to the first ultrasonic transducer;

[0016] The first ultrasonic transducer and the second ultrasonic transducer are used to transmit ultrasonic signals in an alternating cycle; when the first ultrasonic transducer transmits an ultrasonic signal, the second ultrasonic transducer is used to receive a second echo signal, and the third ultrasonic transducer is used to receive a third echo signal; when the second ultrasonic transducer transmits an ultrasonic signal, the first ultrasonic transducer is used to receive a first echo signal;

[0017] The control terminal is also used to determine the time difference between the forward and reverse flow based on the first echo signal and the second echo signal in the same test cycle, determine the first flow rate, and determine the second flow rate based on the third echo signal using the frequency difference method; for the same test cycle, determine the solid particle content level according to the relative size of the second flow rate and the set flow threshold and the difference between the first flow rate and the second flow rate, determine the weights of the first flow rate and the second flow rate, and obtain the weighted average flow rate as the fluid flow rate at the corresponding time.

[0018] Optionally, the control terminal determines the solid particle content level according to the relative size of the second flow rate and the set flow rate threshold and the difference between the first flow rate and the second flow rate, determines the weights of the first flow rate and the second flow rate, and obtains a weighted average flow rate for:

[0019] When the second flow rate is not less than the set flow threshold, if the absolute difference between the first flow rate and the second flow rate is less than the first flow difference threshold, it is determined that the solid particle content is medium, and the weights of the first flow rate and the second flow rate are both determined to be 0.5; if the absolute difference between the first flow rate and the second flow rate is not less than the first flow difference threshold, and not greater than the second flow difference threshold, it is determined that the solid particle content is too little, and the first flow weight is determined to be 1, and the weight of the second flow is determined according to the first calibration result obtained in advance through experiments; if the absolute difference between the first flow rate and the second flow rate is greater than the second flow difference threshold, it is determined that the solid particle content is too much, and the second flow weight is determined to be 1, and the weight of the first flow is determined according to the second calibration result obtained in advance through experiments;

[0020] When the second flow rate is less than the flow threshold, if the absolute difference between the first flow rate and the second flow rate is not less than the first flow difference threshold, it is determined that the solid particle content is extremely small, and the first flow weight is determined to be 1, and the second flow weight is determined to be 0; if the absolute difference between the first flow rate and the second flow rate is less than the first flow difference threshold, an alarm message indicating possible equipment failure is issued.

[0021] Optionally, the traffic threshold is 1 cubic meter per day.

[0022] Optionally, the first flow difference threshold is 0.05 to 0.1 times of the current range, and the second flow difference threshold is 0.15 to 0.2 times of the current range.

[0023] Optionally, the first ultrasonic transducer and the second ultrasonic transducer are both used to directly collect the echo signal after amplifying and filtering it;

[0024] The third ultrasonic transducer is used to amplify and filter the echo signal, mix it with the excitation signal of the first ultrasonic transducer, and then collect it after low-pass filtering through a hardware circuit.

[0025] Optionally, the first, second and third ultrasonic transducers are arranged in the same plane.

[0026] In a second aspect, an embodiment of the present invention provides a wide range ratio ultrasonic flow rate testing method, comprising:

[0027] The ultrasonic signal transceiver of any of the above wide range ratio ultrasonic flow test systems is lowered into the target position of the oil pipe of the target water injection well, and the flow rate of the fluid at the target position in each time period is obtained based on the output data of its control terminal.

[0028] Optionally, obtaining the flow rate of the fluid at the target position in each time period further includes:

[0029] The solid particle content level of the fluid at the target location at each time period is determined.

[0030] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0031] (1) The wide range ratio ultrasonic flow test system provided by the embodiment of the present invention adopts a broadband ultrasonic transducer. When the structural dimensions of the test flow guide tube (especially the size of the flow passage) remain unchanged, the excitation frequency of the ultrasonic transducer is automatically adjusted through the control terminal so that the excitation signal period is greater than the forward and reverse flow time difference. The automatic adjustment of the ultrasonic transducer excitation frequency meets the requirements of a wide span flow test range, greatly expanding the range ratio of the flow test.

[0032] (2) The wide range ratio ultrasonic flow test system provided by the embodiment of the present invention, after the control terminal determines the forward and reverse flow time difference, does not directly use the forward and reverse flow time difference to further determine the fluid flow, but first determines whether the excitation signal periods of the two ultrasonic transducers are both greater than the forward and reverse flow time difference, and whether the absolute difference between the half period of the excitation signal and the forward and reverse flow time difference is less than the set time difference threshold; if not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period meets the above conditions. The control terminal automatically adjusts the excitation frequency of the ultrasonic transducer, and the excitation signal period is greater than the forward and reverse flow time difference, so that the range meets the current measurement requirements; the absolute difference between the half period of the excitation signal and the forward and reverse flow time difference is less than the set time difference threshold, which further ensures the accuracy of the measurement results.

[0033] (3) The wide range ratio ultrasonic flow test system provided by the embodiment of the present invention has a first ultrasonic transducer and a second ultrasonic transducer arranged at a certain axial distance, which are used to transmit ultrasonic signals alternately and cyclically. The first ultrasonic transducer and the third ultrasonic transducer are arranged axially symmetrically, realizing multi-channel downhole flow test, and can determine the first flow by using the time difference method and the second flow by using the frequency difference method; for the same test cycle, the control terminal determines the solid particle content level and the weights of the first flow and the second flow according to the relative size of the second flow and the set flow threshold and the phase difference between the first flow and the second flow, and obtains the weighted average flow as the fluid flow at the corresponding time. The system effectively improves the adaptability of ultrasonic measurement to the purity of the fluid medium and ensures the accuracy and reliability of downhole flow test.

[0034] (4) The wide range ratio ultrasonic flow rate testing system provided in the embodiment of the present invention can effectively monitor the solid particle content level of the downhole injection fluid through the flow rate results tested by the time difference method and the frequency difference method, thereby preventing the problem of the downhole dispenser water channel being blocked by solid particle impurities.

[0035] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0036] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0038] Figure 1 Schematic diagram of the structure of a downhole ultrasonic signal transceiver in a wide turndown ratio ultrasonic flow testing system in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0040] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0041] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which the invention belongs. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0042] In the description of the present invention, it should be noted that the terms "include", "including", "have", "contain" and the like are open terms, meaning including but not limited to.

[0043] In order to solve the problem that the ultrasonic flow test device has a relatively small range and cannot meet the application scenario of wide-range testing, an embodiment of the present invention provides a wide-range ratio ultrasonic flow test system and a test method.

[0044] Embodiment 1

[0045] A first embodiment of the present invention provides a wide-turndown ratio ultrasonic flow rate testing system, comprising a downhole ultrasonic signal transceiver and a ground control terminal.

[0046] The ultrasonic signal transceiver comprises a test flow guide tube, and a first ultrasonic transducer and a second ultrasonic transducer arranged on the test flow guide tube at a certain axial distance. Both ultrasonic transducers are broadband.

[0047] The control terminal is used to determine the forward and reverse flow time difference based on the first echo signal collected by the first ultrasonic transducer and the second echo signal collected by the second ultrasonic transducer in the same test cycle, and judge whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference. If not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference.

[0048] The excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer may be inconsistent; preferably, the excitation frequencies of the two are consistent.

[0049] When the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer are inconsistent, the control terminal determines the excitation signal period according to the excitation frequency of the first ultrasonic transducer, and determines whether the excitation signal period is greater than the forward and reverse flow time difference; determines the excitation signal period according to the excitation frequency of the second ultrasonic transducer, and determines whether the excitation signal period is greater than the forward and reverse flow time difference.

[0050] When the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer are consistent, the control terminal determines the excitation signal period according to the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer, and determines whether the excitation signal period is greater than the forward and reverse flow time difference.

[0051] The excitation signal period of the ultrasonic transducer is greater than the forward and reverse flow time difference, which can ensure that the range meets the current measurement requirements; further, it can also be determined whether the absolute difference between the half period of the excitation signal and the forward and reverse flow time difference is less than the set time difference threshold. If not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference, and the absolute difference between the half period of the excitation signal and the forward and reverse flow time difference is less than the time difference threshold. The forward and reverse flow time difference is close to the half period of the excitation signal, which can further ensure the accuracy of the measurement results.

[0052] The wide range ratio ultrasonic flow test system provided in the first embodiment of the present invention adopts a broadband ultrasonic transducer. When the structural dimensions of the test flow guide tube (especially the size of the flow passage) remain unchanged, the excitation frequency of the ultrasonic transducer is automatically adjusted through the control terminal so that the excitation signal period is greater than the forward and reverse flow time difference. The automatic adjustment of the ultrasonic transducer excitation frequency meets the requirements of a wide span flow test range, greatly expanding the range ratio of the flow test.

[0053] Embodiment 2

[0054] The second embodiment of the present invention provides a wide range ratio ultrasonic flow rate testing system, which is a further improvement on the ultrasonic flow rate testing system described in the first embodiment.

[0055] See also Figure 1 As shown, it is a schematic diagram of the structure of the ultrasonic signal transceiver, which includes a test flow guide tube 4, and a first ultrasonic transducer 1 and a second ultrasonic transducer 2 arranged on the test flow guide tube 4 at a certain axial distance, and also includes a third ultrasonic transducer 3 arranged on the test flow guide tube 4, and the third ultrasonic transducer 3 is axially symmetrically arranged with the first ultrasonic transducer 1.

[0056] Preferably, the first ultrasonic transducer 1 and the second ultrasonic transducer 2 are centrally symmetrically arranged.

[0057] Furthermore, the first, second and third ultrasonic transducers are arranged in the same plane and fixedly installed on both sides of the test flow guide tube by contact installation. Each ultrasonic transducer is provided with an acoustic wedge.

[0058] Figure 1 The arrow in the figure indicates the direction of fluid flow, and the position setting of the three ultrasonic transducers is only an example. Optionally, the first ultrasonic transducer may be located upstream and the second ultrasonic transducer may be located downstream; the third ultrasonic transducer may be axially symmetrical with the second ultrasonic transducer, and so on.

[0059] The first ultrasonic transducer and the second ultrasonic transducer are used to alternately and cyclically transmit ultrasonic signals of a certain frequency; when the first ultrasonic transducer transmits an ultrasonic signal, the second ultrasonic transducer is used to receive a second echo signal and send it to a control terminal, and the third ultrasonic transducer is used to receive a third echo signal and send it to the control terminal; when the second ultrasonic transducer transmits an ultrasonic signal, the first ultrasonic transducer is used to receive the first echo signal and send it to the control terminal.

[0060] by Figure 1 The positions of the three ultrasonic transducers shown in the figure are set as an example for explanation. The specific working principles of the three ultrasonic transducers are as follows:

[0061] The first ultrasonic transducer is driven to emit an ultrasonic signal of a certain frequency, and the two ultrasonic transducers on the other side respectively receive the echo waveform signal and convert it into a voltage signal recognizable by the circuit, wherein the second ultrasonic transducer obtains an upstream echo signal, and the third ultrasonic transducer at the axially symmetrical position obtains a reflected or scattered echo signal; the second ultrasonic transducer is driven to emit an ultrasonic wave, and the first ultrasonic transducer on the other side receives the echo waveform signal to obtain a downstream echo signal.

[0062] The first ultrasonic transducer and the second ultrasonic transducer are both used to directly collect the echo signal after amplifying and filtering it through the hardware circuit; the third ultrasonic transducer is used to amplify and filter the echo signal through the hardware circuit, mix it with the excitation signal of the first ultrasonic transducer, and then collect it after low-pass filtering through the acquisition circuit.

[0063] The control terminal is used to determine the time difference between the forward and reverse flow based on the first echo signal and the second echo signal within the same test cycle, determine the first flow rate, and determine the second flow rate based on the third echo signal using the frequency difference method; for the same test cycle, the solid particle content level is determined according to the relative size of the second flow rate and the set flow threshold and the difference amplitude between the first flow rate and the second flow rate, and the weights of the first flow rate and the second flow rate are determined to obtain the weighted average flow rate as the fluid flow rate at the corresponding time.

[0064] Specifically, the following steps may be included:

[0065] 1. Perform filtering and noise reduction preprocessing on the upstream and downstream echo signals (the first echo signal and the second echo signal) in the same period, and use the adaptive threshold method to calculate the upstream and downstream time and the upstream and downstream time difference of the filtered signals, and then calculate the first flow rate Q1 of the fluid.

[0066] The original echo signals of both upstream and downstream are processed by sliding window mean filtering, with a sliding window size of N. The adaptive threshold method is used to find the first broadcast position of the echo signal after filtering, and the position of the mean value point after the first broadcast position is used as the characteristic point position for calculating the upstream and downstream transmission time of the sound wave, so as to calculate the upstream and downstream time. , Time difference between upstream and downstream , through the upstream and downstream time , , upstream and downstream time difference The first flow rate Q1 is obtained by calculating the installation structure parameters of the transducer guide tube.

[0067] 2. Perform filtering and noise reduction preprocessing on the obtained reflected and / or scattered echo signal (third echo signal), convert the filtered signal from the time domain to the frequency domain, obtain the frequency difference by analyzing its spectrum, and obtain the second flow Q2 by calculating the frequency difference.

[0068] The collected third echo signal, i.e. the frequency shift signal, is subjected to FIR filtering, noise reduction and smoothing processing, and the filtered signal is sampled to obtain the resampled signal, and a fast FFT frequency domain analysis is performed to obtain the final frequency difference. The second flow rate Q2 is calculated by combining the sound wedge sound velocity, the transducer installation structure parameters and the test guide tube structure.

[0069] 3. For the same test cycle, the solid particle content level is determined according to the relative size of the second flow rate and the set flow threshold value and the difference between the first flow rate and the second flow rate, and the weights of the first flow rate and the second flow rate are determined to obtain the weighted average flow rate as the fluid flow rate at the corresponding time.

[0070] The implementation of step 3 above, as shown in Table 1, includes the following situations:

[0071] Table 1 Statistics of solid particle content levels

[0072] (1) When the second flow rate Q2 is not less than the set flow rate threshold S1

[0073] ① If the absolute difference between the first flow rate Q1 and the second flow rate Q2 is less than the first flow rate difference threshold K1, it is determined that the solid particle content is medium, and the weight W1 of the first flow rate and the weight W2 of the second flow rate are both determined to be 0.5.

[0074] First, the second flow rate Q2 is not small enough, indicating that there are certain solid particles in the fluid. At this time, if It is small enough, indicating that the flow rates measured by the time difference method and the frequency difference method are similar, and the solid particle content is determined to be medium, so the weights of the two flow rates are determined to be 0.5.

[0075] ② If the absolute difference between the first flow rate and the second flow rate is not less than the first flow rate difference threshold K1 and not greater than the second flow rate difference threshold K2, it is determined that the solid particle content is too little, and the first flow rate weight W1 is determined to be 1. The second flow rate weight W2 is determined based on the first calibration result obtained in advance through experiments.

[0076] The second flow rate Q2 is not small enough, indicating that there are certain solid particles in the fluid. At this time, if It is neither small enough nor large enough, and it is determined that the solid particle content is too little. The flow rate measured by the time difference method is already close to the actual flow rate, but it is affected by certain solid particles. Therefore, the flow rate measured by the time difference method needs to be corrected using the flow rate measured by the frequency difference method.

[0077] ③ If the absolute difference between the first flow rate and the second flow rate is greater than the second flow rate difference threshold K2, it is determined that the solid particle content is too high, and the second flow rate weight W2 is determined to be 1. The weight W1 of the first flow rate is determined according to the second calibration result obtained in advance through experiments.

[0078] The second flow rate Q2 is not small enough, indicating that there are certain solid particles in the fluid. At this time, if It is large enough to determine that the solid particle content is too high. The flow rate measured by the frequency difference method is closer to the actual flow rate. Therefore, the flow rate measured by the frequency difference method needs to be corrected using the flow rate measured by the time difference method.

[0079] (2) When the second flow rate is less than the flow threshold S1

[0080] ① If the absolute difference between the first flow rate Q1 and the second flow rate Q2 is not less than a flow difference threshold K1, it is determined that the solid particle content is very small, and the first flow rate weight W1 is determined to be 1, and the second flow rate weight W2 is determined to be 0.

[0081] First, if the second flow rate Q2 is small enough, it means that there are fewer solid particles in the fluid, and the flow rate measured by the frequency difference method will be relatively small in theory. It is not too small, which means that the flow rates measured by the time difference method and the frequency difference method are not so close. The flow rate measured by the time difference method is more accurate, and the solid particle content is determined to be extremely small. The first flow weight W1 is determined to be 1, and the second flow weight W2 is determined to be 0.

[0082] ② If the absolute difference between the first flow rate Q1 and the second flow rate Q2 is less than the first flow difference threshold K1, an alarm message indicating a possible equipment failure is issued.

[0083] First, if the second flow rate Q2 is small enough, it means that there are fewer solid particles in the fluid, and the flow rate measured by the frequency difference method will be relatively small in theory. It is small enough, which means that the flow rates measured by the time difference method and the frequency difference method are similar. That is, the flow rate measured by the time difference method is also small, which is obviously inconsistent with the reality, indicating the possibility of machine failure.

[0084] In some embodiments, the first flow difference threshold is determined to be 0.05 to 0.1 times the current range of the system, and the second flow difference threshold is determined to be 0.15 to 0.2 times the current range of the system; the flow threshold is determined to be 1 cubic meter / day.

[0085] In the wide range ratio ultrasonic flow test system provided by the second embodiment of the present invention, the first ultrasonic transducer and the second ultrasonic transducer are arranged at a certain axial distance, and are used to transmit ultrasonic signals alternately and cyclically. The first ultrasonic transducer and the third ultrasonic transducer are arranged axially symmetrically, realizing multi-channel downhole flow test, and can determine the first flow by the time difference method, and determine the second flow by the frequency difference method; for the same test cycle, the control terminal determines the solid particle content level according to the relative size of the second flow and the set flow threshold and the phase difference amplitude between the first flow and the second flow, determines the weight of the first flow and the second flow, and obtains the weighted average flow as the fluid flow at the corresponding time. The system effectively improves the adaptability of ultrasonic measurement to the purity of the fluid medium, and ensures the accuracy and reliability of downhole flow test.

[0086] The wide range ratio ultrasonic flow testing system provided in the second embodiment of the present invention can effectively monitor the solid particle content level of the downhole injection fluid through the flow results tested by the time difference method and the frequency difference method, thereby preventing the problem of the downhole dispenser water channel being blocked by solid particle impurities.

[0087] Based on the inventive concept of the present invention, an embodiment of the present invention further provides a wide range ratio ultrasonic flow rate testing method, comprising:

[0088] The ultrasonic signal transceiver of any of the above wide range ratio ultrasonic flow test systems is lowered into the target position of the oil pipe of the target water injection well, and the flow rate of the fluid at the target position in each time period is obtained based on the output data of its control terminal.

[0089] Optionally, obtaining the flow rate of the fluid at the target position in each time period further includes:

[0090] The solid particle content level of the fluid at the target location at each time period is determined.

[0091] For situations where the flow rate changes are not too large, the forward and reverse flow time difference can be calculated in advance based on the angles and axial distances of the first and second transducers, the maximum flow velocity of the fluid and the speed of sound, and the transducer excitation frequency can be set. A relatively low frequency is used for large flow rates, and a relatively high frequency is used for small flow rates. The transducer works under the excitation of this fixed frequency signal.

[0092] For situations where the flow rate changes greatly, during the initial measurement, the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer can be adjusted to a sufficiently low level through the control terminal, and the forward and reverse flow time difference at the frequency can be tested. The control terminal then automatically determines the excitation frequency suitable for the flow rate based on the tested time difference value to ensure that it is within the optimal flow measurement range.

[0093] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0094] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0095] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to represent "non-exclusive or". The terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

Claims

1. A wide range ratio ultrasonic flow test system, characterized in that: It includes a downhole ultrasonic signal transceiver and a ground control terminal; The ultrasonic signal transceiver comprises a test flow guide tube, and a first ultrasonic transducer and a second ultrasonic transducer arranged on the test flow guide tube at a certain axial distance; The control terminal is used to determine the forward and reverse flow time difference based on the first echo signal collected by the first ultrasonic transducer and the second echo signal collected by the second ultrasonic transducer in the same test cycle, and judge whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference; if not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference.

2. The system according to claim 1, characterized in that The control terminal determines whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, and is used to: Determine an excitation signal period according to the excitation frequency of the first ultrasonic transducer, and judge whether the excitation signal period is greater than the forward and reverse flow time difference; The excitation signal period is determined according to the excitation frequency of the second ultrasonic transducer, and it is determined whether the excitation signal period is greater than the forward and reverse flow time difference.

3. The system according to claim 1, characterized in that The excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer are consistent, and the control terminal determines whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, for: The excitation signal period is determined according to the excitation frequencies of the first ultrasonic transducer and the second ultrasonic transducer, and it is judged whether the excitation signal period is greater than the forward and reverse flow time difference.

4. The system according to claim 2 or 3, characterized in that The control terminal determines whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, and if not, adjusts the excitation frequency of the corresponding ultrasonic transducer so that the excitation signal period is greater than the forward and reverse flow time difference, for: Determine whether the excitation signal periods of the first ultrasonic transducer and the second ultrasonic transducer are both greater than the forward and reverse flow time difference, and whether the absolute difference between the excitation signal half period and the forward and reverse flow time difference is both less than a set time difference threshold; If not, adjust the excitation frequency of the corresponding ultrasonic transducer so that its excitation signal period is greater than the forward and reverse flow time difference, and the absolute difference between the excitation signal half period and the forward and reverse flow time difference is less than the time difference threshold.

5. The system according to claim 3, characterized in that The ultrasonic signal transceiver device further includes a third ultrasonic transducer disposed on the test flow guide tube, wherein the third ultrasonic transducer is axially symmetrically disposed with respect to the first ultrasonic transducer; The first ultrasonic transducer and the second ultrasonic transducer are used to transmit ultrasonic signals in an alternating cycle; when the first ultrasonic transducer transmits an ultrasonic signal, the second ultrasonic transducer is used to receive a second echo signal, and the third ultrasonic transducer is used to receive a third echo signal; when the second ultrasonic transducer transmits an ultrasonic signal, the first ultrasonic transducer is used to receive a first echo signal; The control terminal is also used to determine the time difference between the forward and reverse flow based on the first echo signal and the second echo signal in the same test cycle, determine the first flow rate, and determine the second flow rate based on the third echo signal using the frequency difference method; for the same test cycle, determine the solid particle content level according to the relative size of the second flow rate and the set flow threshold and the difference between the first flow rate and the second flow rate, determine the weights of the first flow rate and the second flow rate, and obtain the weighted average flow rate as the fluid flow rate at the corresponding time.

6. The system according to claim 5, characterized in that The control terminal determines the solid particle content level and the weights of the first flow rate and the second flow rate according to the relative size of the second flow rate and the set flow rate threshold and the difference between the first flow rate and the second flow rate, and obtains a weighted average flow rate for: When the second flow rate is not less than the set flow threshold, if the absolute difference between the first flow rate and the second flow rate is less than the first flow difference threshold, it is determined that the solid particle content is medium, and the weights of the first flow rate and the second flow rate are both determined to be 0.5; if the absolute difference between the first flow rate and the second flow rate is not less than the first flow difference threshold, and not greater than the second flow difference threshold, it is determined that the solid particle content is too little, and the first flow weight is determined to be 1, and the weight of the second flow is determined according to the first calibration result obtained in advance through experiments; if the absolute difference between the first flow rate and the second flow rate is greater than the second flow difference threshold, it is determined that the solid particle content is too much, and the second flow weight is determined to be 1, and the weight of the first flow is determined according to the second calibration result obtained in advance through experiments; When the second flow rate is less than the flow threshold, if the absolute difference between the first flow rate and the second flow rate is not less than the first flow difference threshold, it is determined that the solid particle content is extremely small, and the first flow weight is determined to be 1, and the second flow weight is determined to be 0; if the absolute difference between the first flow rate and the second flow rate is less than the first flow difference threshold, an alarm message indicating possible equipment failure is issued.

7. The system according to claim 6, characterized in that The traffic threshold is 1 cubic meter per day.

8. The system according to claim 6, characterized in that The first flow difference threshold is 0.05 to 0.1 times of the current range, and the second flow difference threshold is 0.15 to 0.2 times of the current range.

9. The system according to claim 5, characterized in that The first ultrasonic transducer and the second ultrasonic transducer are both used to directly collect the echo signal after amplifying and filtering; The third ultrasonic transducer is used to amplify and filter the echo signal, mix it with the excitation signal of the first ultrasonic transducer, and then collect it after low-pass filtering through a hardware circuit.

10. The system according to claim 5, characterized in that The first, second and third ultrasonic transducers are arranged in the same plane.

11. A wide range ratio ultrasonic flow rate testing method, characterized in that: include: The ultrasonic signal transceiver of the wide range ratio ultrasonic flow test system according to any one of claims 1 to 10 is lowered into the target position of the oil pipe of the target water injection well, and the flow rate of the fluid at the target position in each time period is obtained based on the output data of its control terminal.

12. The method according to claim 11, characterized in that The step of obtaining the flow rate of the fluid at the target position in each time period further includes: The solid particle content level of the fluid at the target location at each time period is determined.

Images