CN109281651B - Ultrasonic borehole wall imaging method applied to cylindrical surface ultrasonic array - Google Patents
Ultrasonic borehole wall imaging method applied to cylindrical surface ultrasonic array Download PDFInfo
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- CN109281651B CN109281651B CN201710589594.8A CN201710589594A CN109281651B CN 109281651 B CN109281651 B CN 109281651B CN 201710589594 A CN201710589594 A CN 201710589594A CN 109281651 B CN109281651 B CN 109281651B
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/002—Survey of boreholes or wells by visual inspection
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
- E21B47/14—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
Abstract
The invention relates to an ultrasonic borehole wall imaging method applied to a cylindrical ultrasonic array, which comprises the following steps: step 1) driving each transducer array element in the cylindrical surface ultrasonic array to sequentially and independently transmit ultrasonic signals, and simultaneously receiving echo signals corresponding to each transmitted signal by all the transducer array elements; step 2) utilizing the echo signals obtained in the step 1) to carry out point-by-point focusing imaging processing on each imaging point according to a synthetic aperture focusing algorithm to obtain echo amplitude data corresponding to each imaging point; and step 3) splicing the echo amplitude data corresponding to each imaging point together to obtain an amplitude imaging graph in the whole imaging plane. The ultrasonic borehole wall imaging method is applied to ultrasonic borehole wall detection, the number of independent channels of a cylindrical array ultrasonic borehole wall imaging system is greatly reduced, and the hardware cost of the system is reduced; meanwhile, the resolution of borehole wall imaging detection can be improved under the condition that the frequency of the underground transducer is low.
Description
Technical Field
The invention relates to the technical field of ultrasonic borehole wall imaging, in particular to an ultrasonic borehole wall imaging method applied to a cylindrical surface ultrasonic array.
Background
The ultrasonic borehole wall imaging detection technology utilizes amplitude information extracted by the reflection echo of the borehole wall or the casing wall to clearly and visually display the condition of the borehole wall in the form of an echo amplitude diagram. Compared with the traditional ultrasonic borehole wall imaging detection technology, the cylindrical array ultrasonic borehole wall imaging detection technology has the advantages of avoiding probe rotation, being adjustable in focus point and the like, and has attracted extensive attention in recent years. The existing cylindrical surface array ultrasonic borehole wall imaging adopts a phased array imaging technology, the transmitting acoustic beam of a cylindrical surface array transducer is focused on the borehole wall by controlling the transmitting and receiving time delay of each independent channel, the reflected echo on the focusing point is received, the peak value of the echo is taken as the amplitude value of the imaging point and finally reflected in the borehole wall amplitude imaging graph.
At present, a phased array method is mostly adopted for underground cylindrical surface array imaging, and the phased array for borehole wall imaging requires n array elements to transmit or receive signals simultaneously, so that the underground system is required to have corresponding hardware channel number (n paths), and the complexity and the instability of the underground system design are increased. The above phased array imaging techniques have specific drawbacks including: 1) because the space is narrow in the pit, the integrated circuit board wiring of array supersound wall of a well imaging detection electronic system that has numerous independent passageway is difficult, 2) because consider the mud decay characteristic in the pit, the array transducer central frequency who adopts in the wall of a well imaging detection can not select too high, and this has restricted the promotion of wall of a well imaging detection precision to a certain extent.
Disclosure of Invention
The invention aims to solve the technical problems of complex board wiring and low detection precision of the conventional phased array imaging technology, and provides an ultrasonic borehole wall imaging method applied to a cylindrical ultrasonic array. Meanwhile, the resolution of borehole wall imaging detection can be improved under the condition that the frequency of the underground transducer is low.
In order to solve the above problems, the present invention provides an ultrasonic borehole wall imaging method applied to a cylindrical ultrasonic array, which comprises:
step 1) driving each transducer array element in the cylindrical surface ultrasonic array to sequentially and independently transmit ultrasonic signals, and simultaneously receiving echo signals corresponding to each transmitted signal by all the transducer array elements;
step 2) utilizing the echo signals obtained in the step 1) to carry out point-by-point focusing imaging processing on each imaging point according to a synthetic aperture focusing algorithm to obtain echo amplitude data corresponding to each imaging point; and
and 3) splicing the echo amplitude data corresponding to each imaging point together to obtain an amplitude imaging graph in the whole imaging plane.
As a further improvement of the above technical solution, the step 2) specifically includes:
step 101) carrying out time delay processing on all echo signals obtained in step 1) according to a synthetic aperture focusing algorithm to obtain a plurality of time delay echo signals corresponding to each imaging point in a scanning plane;
step 102) carrying out superposition calculation on a plurality of delay echo signals corresponding to each imaging point;
step 103) enveloping the echo signals after superposition calculation to obtain enveloping signals corresponding to each imaging point;
and 104) carrying out peak judgment on the envelope signals corresponding to the imaging points, and selecting peak data in the envelope signals as amplitude data of the imaging points.
As a further improvement of the above technical solution, in step 101), a delay value calculation formula of the echo signal is expressed as:
wherein, T is the position coordinate of the transmitting array element, R is the position coordinate of the receiving array element, P is the position coordinate of the imaging point in the scanning plane, and c is the medium sound velocity.
As a further improvement of the above technical solution, the echo signal after the superposition calculation in step 102) is represented as:
the position coordinates of an imaging point in a scanning plane are expressed as (x, z), l represents the ith transmitting array element, m represents the mth receiving array element, and n represents the number of transducer array elements in the driving cylindrical ultrasonic array.
As a further improvement of the above technical solution, the step 103) specifically includes: firstly, the hubert transform is calculated for the echo signal I (x, z) corresponding to each imaging point after superposition calculation, so as to obtain the imaginary part of the complex signal corresponding to the echo signal I (x, z), and the calculation formula of the imaginary part is expressed as:
wherein t represents time, and the above formula corresponds to time signals of each point;
then, the imaginary part is used to calculate the mode of the echo signal I (x, z) corresponding to the complex signal, and the envelope signal corresponding to each imaging point is obtained, and the calculation formula of the envelope signal is expressed as:
where a represents the envelope signal at the imaging point coordinates (x, z).
The ultrasonic borehole wall imaging technology is a key technology for borehole wall imaging detection, and reasonable imaging technology improvement can effectively reduce system complexity and improve imaging detection precision. The synthetic aperture focused ultrasound imaging technology utilizes a small aperture transducer to synthesize an equivalent large aperture, and can obtain satisfactory resolution under the conditions of less channel number of a hardware system and lower central frequency of the transducer. Therefore, the synthetic aperture technology is applied to the cylindrical surface array ultrasonic borehole wall imaging detection, the number of channels of an array ultrasonic system can be greatly saved, the cost and the difficulty of design of an underground electronic hardware system are reduced, and meanwhile, the resolution of borehole wall imaging detection can be improved under the condition that the frequency of an underground transducer is low.
The ultrasonic borehole wall imaging method applied to the cylindrical ultrasonic array has the advantages that:
the ultrasonic borehole wall imaging method provided by the invention is used for acquiring original echo data received when each array element is sequentially and independently transmitted by utilizing a synthetic aperture full-focusing mode according to the characteristics of a cylindrical ultrasonic array transducer array element and the actual borehole wall detection situation, carrying out point-by-point focusing imaging processing on each imaging point so as to obtain echo amplitude data corresponding to each imaging point, and splicing the echo amplitude data of each imaging point together to obtain an amplitude imaging image in the whole imaging plane. The invention is applied to ultrasonic borehole wall imaging detection, greatly reduces the number of independent channels of a cylindrical array ultrasonic borehole wall imaging system, and reduces the hardware cost of the system. Meanwhile, the resolution of borehole wall imaging detection can be improved under the condition that the frequency of the underground transducer is low.
Drawings
FIG. 1 is a schematic diagram of a cylindrical array transducer according to the present invention;
FIG. 2 is a schematic diagram of the working flow of the cylindrical array synthetic aperture focusing imaging method of the present invention;
fig. 3 is a flowchart of the operation of the cylindrical array synthetic aperture focusing imaging method in the present invention.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings and embodiments.
The ultrasonic borehole wall imaging method provided by the invention is used for acquiring original echo data received when each array element is sequentially and independently transmitted by utilizing a synthetic aperture full-focusing mode according to the characteristics of a cylindrical ultrasonic array transducer array element and the actual borehole wall detection situation, carrying out point-by-point focusing imaging processing on each imaging point so as to obtain echo amplitude data corresponding to each imaging point, and splicing the echo amplitude data of each imaging point together to obtain an amplitude imaging image in the whole imaging plane.
The synthetic aperture principle is that the synthetic aperture technology is applied to the underground cylindrical surface array imaging by utilizing the equivalent large aperture imaging effect of small apertures at different positions, the imaging resolution equivalent to that of the phased array method can be obtained by utilizing less hardware channels, and further the complexity of the design of an underground system is reduced. Therefore, the invention provides a synthetic aperture ultrasonic borehole wall imaging method applied to a cylindrical array, the structure of a cylindrical array transducer adopted by the method is shown in figure 1, and N strip-shaped piezoelectric wafers are uniformly distributed on the surface of a cylindrical structure. When the transducer works, n array elements are used as a dynamic array element group, and signal transmitting, receiving and synthetic aperture focusing imaging algorithm processing are carried out according to the group.
The ultrasonic borehole wall imaging method specifically comprises the following steps:
step 1) driving each transducer array element in the cylindrical surface ultrasonic array to sequentially and independently transmit ultrasonic signals, and simultaneously receiving echo signals corresponding to each transmitted signal by all the transducer array elements;
step 2) utilizing the echo signals obtained in the step 1) to carry out point-by-point focusing imaging processing on each imaging point according to a synthetic aperture focusing algorithm to obtain echo amplitude data corresponding to each imaging point; and
and 3) splicing the echo amplitude data corresponding to each imaging point together to obtain an amplitude imaging graph in the whole imaging plane.
Example one
In this example, the workflow of performing ultrasonic borehole wall imaging by using the synthetic aperture focusing method specifically includes the following two operations:
(1) the control of ultrasonic emission and echo reception and the acquisition of original echo signals are completed on the current dynamic array element group, and the system control work flow in the process is shown in fig. 2. The dynamic array element group comprises n array elements, wherein the number 1 array element transmits ultrasonic signals for the first time, the number 1-n array elements (namely, the full aperture) receive echo signals, the number 2 array element transmits ultrasonic signals for the second time, the full aperture receives echo signals, and the rest is done by analogy until the last array element transmits ultrasonic signals for the nth time, and the full aperture receives echo signals. The echo signal set obtained by the current dynamic array element group contains the combination relation of all single array element emission and all array element reception, so that when the dynamic array element group is completed, n is obtained2Original echo signal sl,m(t) (l 1,2, …, n; m 1,2, …, n) and storing the raw echo signals for subsequent synthetic aperture focused imaging signal processing.
(2) The signal processing of the synthetic aperture focusing imaging method is performed on the acquired original echo signal, and the algorithm flow is shown in fig. 3. The detailed steps in the signal processing process include:
step 1) obtaining n from current dynamic array tuple2The original echo signals are delayed according to a synthetic aperture focusing rule, and the delay value of each echo signal is obtained by calculation according to the following formula:
wherein T is the position coordinate of the transmitting array element, R is the position coordinate of the receiving array element, P is the position coordinate of the imaging point in the scanning plane, and c is the sound velocity in the medium.
Step 2) performing superposition calculation on the delayed signals, wherein the expression of the superposed echo signals is as follows:
and (x, z) is the position coordinate of an imaging point in a scanning plane, l represents the l-th transmitting array element, m represents the m-th receiving array element, and n represents the number of transducer array elements in the driving cylindrical ultrasonic array.
And 3) enveloping the superposed echo signals I (x, z).
The specific method is that Hilbert transform is firstly obtained for echo signals I (x, z), so as to obtain imaginary parts of complex signals corresponding to the echo signals I (x, z), and a calculation formula of the imaginary parts is expressed as:
then, the mode of the complex signal can be obtained from the trigonometric function property, that is, the mode of the complex signal corresponding to the echo signal I (x, z) is calculated by using the imaginary part, so as to obtain the envelope signal corresponding to each imaging point, and the calculation formula of the envelope signal is expressed as:
wherein, a is an envelope signal of the echo signal I (x, z) after the superposition at the imaging point coordinates (x, z).
And 4) carrying out peak value judgment on the envelope signal E (x, z) to be used as amplitude data on the coordinates (x, z) of the imaging point.
In actual processing, assuming that the digitized envelope signal E (x, z) is x (n), if there is a point x (i) such that there is x (i) > x (n) for any n (n ≠ i) in the sequence x (n), then x (i) is taken as the amplitude data at the imaging point coordinates (x, z).
And 5) splicing the amplitude data on each imaging point obtained by calculation in the step to obtain a final cylindrical array synthetic aperture focusing imaging graph. If a dynamic array element group corresponds to a scanning circumference mthFor each imaging point, the cylindrical array circumferential scanning area has N multiplied by mthAnd (4) imaging the dots.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (2)
1. An ultrasonic borehole wall imaging method applied to a cylindrical ultrasonic array is characterized by comprising the following steps:
step 1) driving each transducer array element in the cylindrical surface ultrasonic array to sequentially and independently transmit ultrasonic signals, and simultaneously receiving echo signals corresponding to each transmitted signal by all the transducer array elements;
step 2) utilizing the echo signals obtained in the step 1) to carry out point-by-point focusing imaging processing on each imaging point according to a synthetic aperture focusing algorithm to obtain echo amplitude data corresponding to each imaging point; and
step 3) splicing echo amplitude data corresponding to each imaging point together to obtain an amplitude imaging graph in the whole imaging plane;
the step 2) specifically comprises the following steps:
step 101) carrying out time delay processing on all echo signals obtained in step 1) according to a synthetic aperture focusing algorithm to obtain a plurality of time delay echo signals corresponding to each imaging point in a scanning plane;
step 102) carrying out superposition calculation on a plurality of delay echo signals corresponding to each imaging point;
step 103) enveloping the echo signals after superposition calculation to obtain enveloping signals corresponding to each imaging point;
step 104) carrying out peak judgment on the envelope signals corresponding to the imaging points, and selecting peak data in the envelope signals as amplitude data of the imaging points;
the delay value calculation formula of the echo signal in the step 101) is expressed as follows:
wherein T is the position coordinate of the transmitting array element, R is the position coordinate of the receiving array element, P is the position coordinate of the imaging point in the scanning plane, and c is the medium sound velocity;
the echo signals after superposition calculation in the step 102) are represented as:
wherein the position coordinate of the imaging point in the scanning plane is represented as Px,zL denotes the l-th transmitting array element, RlCoordinates representing the ith transmitting array element; m denotes the mth receiving array element, TmCoordinates representing the m-th receiving array element; n represents the number of transducer elements in the driven cylindrical ultrasound array, sm,l(t) is the original echo signal, l ═ 1,2, …, n; m is 1,2, …, n.
2. The method of claim 1, wherein said step 103) comprises: firstly, the hubert transform is calculated for the echo signal I (x, z) corresponding to each imaging point after superposition calculation, so as to obtain the imaginary part of the complex signal corresponding to the echo signal I (x, z), and the calculation formula of the imaginary part is expressed as:
wherein t represents time;
then, the imaginary part is used to calculate the mode of the echo signal I (x, z) corresponding to the complex signal, and the envelope signal corresponding to each imaging point is obtained, and the calculation formula of the envelope signal is expressed as:
where a represents the envelope signal at the imaging point coordinates (x, z).
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| CN110837126B (en) * | 2019-11-26 | 2021-11-23 | 内蒙古工业大学 | Signal receiving and transmitting method and device for cylindrical array radar imaging |
| CN113552573B (en) * | 2021-06-29 | 2022-07-29 | 复旦大学 | Rapid imaging algorithm based on ultrasonic ring array synthetic aperture receiving |
| CN113567992A (en) * | 2021-08-02 | 2021-10-29 | 国网吉林省电力有限公司四平供电公司 | Method and system for detecting inner lead of transformer bushing focused by ultrasonic synthetic aperture |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1112639A (en) * | 1994-05-26 | 1995-11-29 | 魏营隆 | Drill bit central coordinate ultrasonic wave real-time measurement while drilling for large driller |
| CN101493438A (en) * | 2009-02-18 | 2009-07-29 | 宁波工程学院 | Phased array ultrasonic detection, data acquisition and process device |
| CN202031567U (en) * | 2011-01-05 | 2011-11-09 | 中国海洋石油总公司 | Circuit used for measuring annulus instantaneous flow in marine riser |
| CN103969651A (en) * | 2014-04-24 | 2014-08-06 | 中国科学院声学研究所 | Self-adaptive acoustic imaging method |
| CN104330480A (en) * | 2013-07-22 | 2015-02-04 | 中国科学院声学研究所 | Fault diagnosis method for ultrasonic phased array imaging detector |
-
2017
- 2017-07-19 CN CN201710589594.8A patent/CN109281651B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1112639A (en) * | 1994-05-26 | 1995-11-29 | 魏营隆 | Drill bit central coordinate ultrasonic wave real-time measurement while drilling for large driller |
| CN101493438A (en) * | 2009-02-18 | 2009-07-29 | 宁波工程学院 | Phased array ultrasonic detection, data acquisition and process device |
| CN202031567U (en) * | 2011-01-05 | 2011-11-09 | 中国海洋石油总公司 | Circuit used for measuring annulus instantaneous flow in marine riser |
| CN104330480A (en) * | 2013-07-22 | 2015-02-04 | 中国科学院声学研究所 | Fault diagnosis method for ultrasonic phased array imaging detector |
| CN103969651A (en) * | 2014-04-24 | 2014-08-06 | 中国科学院声学研究所 | Self-adaptive acoustic imaging method |
Non-Patent Citations (4)
| Title |
|---|
| 石油钻井中超声相控阵井壁成像检测技术研究;董晗等;《机械工程学报》;20161025;第52卷(第22期);第1-8页 * |
| 超声相控阵井壁成像检测的回波信号处理;董晗等;《无损检测》;20170510(第5期);超声相控阵井壁成像检测的回波信号处理 * |
| 超声相控阵系统中高精度相控发射和相控信号并行处理的实现;孔超等;《无损检测》;20101210(第12期);第966-969、993页 * |
| 高精度波束形成的相控阵超声系统研究;李杏华等;《传感技术学报》;20170331;第30卷(第3期);第471-476页 * |
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