CN113033113A - Prediction method for movement space size of perforating fluid of packing section - Google Patents
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Abstract
The invention provides a method for predicting the movement space size of perforating fluid of a packing section, which comprises the following steps: establishing a control equation set of motion interaction of the detonation gas and the perforating fluid in the packing section, and obtaining a perforating fluid pressure wave propagation motion equation set based on the control equation set; based on a motion equation set of the perforating fluid under the action of detonation gas, utilizing an underwater explosion theory, obtaining a perforating fluid compression velocity equation by analyzing the volume compressibility of the perforating fluid, and obtaining an upward motion equation of the perforating fluid according to a hydraulic theory and a Newton's second law; and calculating the compression movement speed and the upward movement speed of the perforating fluid, and predicting the movement space size of the perforating fluid in the packing section. The physical modeling and numerical calculation adopted in the prediction method provide a space size prediction method, which not only can ensure the prediction precision of the movement space size of the perforating fluid in the packing section, but also can obtain the change rule of the movement speed of the perforating fluid along with time under the perforating impact effect, thereby providing a theoretical basis for scientific perforating design.
Description
Technical Field
The invention relates to the field of oil and gas well engineering perforation, in particular to a prediction method for the movement space size of packer section perforating fluid.
Background
The safety problem of the perforating shaft is not ignored, particularly for deep water and ultra-deep water perforating test operation, comprehensive consideration and careful preparation are required, and safety of downhole tools and equipment in the operation process is guaranteed. Otherwise, any minor problem may occur with unforeseeable consequences. In the deep water perforation test process at home and abroad, the following packer failure modes are frequently generated: the upper part or the lower part of the packer is lost, the central pipe is broken, the sealing is invalid, the well is loosened when being shut down, the packer is directly unsealed, the packer is easy to set, the well is clamped, the service life is shortened, and the like.
The direct reasons for these failure modes are that when the perforating bullet explodes in a liquid-filled wellbore, the formed detonation product rapidly expands in the liquid in the wellbore in the form of gas, and strongly compresses adjacent fluid, so that the pressure and temperature of the adjacent fluid are rapidly increased to form an initial pressure wave, the movement speed of the initial pressure wave is approximately equal to the sound velocity, the initial pressure wave reciprocates for multiple times in the space between the packer and the bottom of the well, the expansion effect of the detonation product and the formed high-energy gas has a large influence on the movement of perforating fluid, and the movement condition of the perforating fluid directly influences the safety of the packer.
At present, the research on the movement space size of the perforating fluid of the packer section is less in China, a prediction method for the movement space size of the perforating fluid of the packer section is lacked, and the movement condition of the perforating fluid of the packer section has direct influence on the safety of the perforating fluid under the perforation working condition. Therefore, a method for predicting the movement space of perforating fluid in the packer section is needed to be provided, so that the safety of the packer under the perforation working condition is improved, and powerful technical support is provided for the safety of site perforation operation.
Disclosure of Invention
The invention provides a method for predicting the movement space size of packer perforating fluid, which overcomes or at least partially solves the problems, and comprises the following steps: establishing a one-dimensional model of the pressure field of the shaft of the oil pipe section during perforation by analyzing the physical process of the pressure field of the shaft of the oil pipe section and assuming conditions; analyzing a one-dimensional model of a pressure field of a shaft of the oil pipe section during perforation, and establishing a control equation set of motion interaction of detonation gas and perforating fluid of the perforating section, wherein the control equation set comprises a relation equation set of pressure, speed, sectional area of the shaft and density along with time and position change; converting the control equation set into a full differential equation set; resolving the full differential equation set to obtain a perforating fluid pressure wave propagation motion equation set, and analyzing to obtain a motion equation set of the perforating fluid under the action of detonation gas after analyzing the change condition of the pressure wave generated by the detonation gas in the packing section; based on the motion equation set of the perforating fluid under the action of detonation gas, obtaining a perforating fluid compression velocity equation by analyzing the volume compressibility of the perforating fluid by using an underwater explosion theory, and obtaining an upward motion equation of the perforating fluid according to a hydraulic theory and a Newton's second law; calculating the compression movement speed of the perforating fluid when the perforating fluid is compressed according to a perforating fluid compression speed equation, and calculating the upward movement speed of the perforating fluid after the perforating fluid is decompressed according to a perforating fluid upward movement equation; and predicting the movement space size of the perforating fluid of the packing section according to the compression movement speed of the perforating fluid and the upward movement speed of the perforating fluid.
The method for predicting the movement space size of the perforating fluid of the packing section provided by the invention adopts physical modeling and numerical calculation to provide a space size prediction method, can ensure the prediction precision of the movement space size of the perforating fluid of the packing section, obtains the change rule of the movement speed of the perforating fluid along with time under the action of perforating impact, and provides a theoretical basis for scientific perforating design.
Drawings
FIG. 1 is a flow chart of a method for predicting the movement space of perforating fluid in a packer section according to the present invention;
FIG. 2 is a simplified schematic diagram of a physical model of a prediction method of the movement space size of perforating fluid in a packing section;
FIG. 3 is a simplified schematic diagram of a physical model of a prediction method of the movement space size of perforating fluid in a packing section;
FIG. 4 is a graph of perforation fluid compression rate versus time;
fig. 5 is a graph of perforation fluid rise rate versus time.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Fig. 1 is a flowchart of a method for predicting the movement space size of perforating fluid in an isolation section, as shown in fig. 1, the method includes: 101. establishing a one-dimensional model of the pressure field of the shaft of the oil pipe section during perforation by analyzing the physical process of the pressure field of the shaft of the oil pipe section and assuming conditions; 102. Analyzing a one-dimensional model of a pressure field of a shaft of the oil pipe section during perforation, and establishing a control equation set of motion interaction of detonation gas and perforating fluid of the perforating section, wherein the control equation set comprises a relation equation set of pressure, speed, sectional area of the shaft and density along with time and position change; 103. Converting the control equation set into a full differential equation set; 104. resolving the full differential equation set to obtain a perforating fluid pressure wave propagation motion equation set, and analyzing to obtain a motion equation set of the perforating fluid under the action of detonation gas after analyzing the change condition of the pressure wave generated by the detonation gas in the packing section; 105. based on the motion equation set of the perforating fluid under the action of detonation gas, obtaining a perforating fluid compression velocity equation by analyzing the volume compressibility of the perforating fluid by using an underwater explosion theory, and obtaining an upward motion equation of the perforating fluid according to a hydraulic theory and a Newton's second law; 106. calculating the compression movement speed of the perforating fluid when the perforating fluid is compressed according to a perforating fluid compression speed equation, and calculating the upward movement speed of the perforating fluid after the perforating fluid is decompressed according to a perforating fluid upward movement equation; 107. and predicting the movement space size of the perforating fluid of the packing section according to the compression movement speed of the perforating fluid and the upward movement speed of the perforating fluid.
Based on the problems in the background art, the invention provides a method for predicting the change rule of the movement speed of perforating fluid in a shaft of an oil pipe section along with time during perforating, which meets the requirements of actual conditions and can be used for more accurately predicting the size of the movement space of the perforating fluid in a packer section.
In the process of perforation, as can be seen from fig. 2 and 3, the packer and the wellbore form a complete closed space in the downhole, and when the perforating bullet explodes in the wellbore filled with liquid, the formed detonation products rapidly expand in the liquid in the wellbore in the form of gas, and strongly compress adjacent fluids, so that in the simplified schematic diagrams of fig. 2 and 3, the fluid micelles are further compressed under the action of the impact force in the upward direction and the gravity of the fluid micelles.
Establishing a control equation set of motion interaction of the detonation gas and the perforating fluid in the packing section, and obtaining a perforating fluid pressure wave propagation motion equation set based on the control equation set; based on a motion equation set of the perforating fluid under the action of detonation gas, utilizing an underwater explosion theory, obtaining a perforating fluid compression velocity equation by analyzing the volume compressibility of the perforating fluid, and obtaining an upward motion equation of the perforating fluid according to a hydraulic theory and a Newton's second law; and calculating the compression movement speed and the upward movement speed of the perforating fluid, and predicting the movement space size of the perforating fluid in the packing section. The physical modeling and numerical calculation adopted in the prediction method provide a space size prediction method, which not only can ensure the prediction precision of the movement space size of the perforating fluid in the packing section, but also can obtain the change rule of the movement speed of the perforating fluid along with time under the perforating impact effect, thereby providing a theoretical basis for scientific perforating design.
In a possible embodiment mode, when a one-dimensional model of a pressure field in a shaft of a tubing section during perforation is established, the process of forming jet flow by perforation is analyzed, a complex three-dimensional movement process of perforation is formed in the time period, and the main purpose of research is to study the influence of the movement situation of perforating fluid in the shaft on the safety of a packer, so that the physical phenomenon is simplified under the assumed condition according to the main purpose, and the movement of the perforating fluid is determined to be one-dimensional irregular plane movement.
The method comprises the following steps of establishing a one-dimensional model of the pressure field of the shaft of the oil pipe section during perforation through physical process analysis and condition assumption of the pressure field of the shaft of the oil pipe section, and specifically comprises the following steps: (1) determining hypothetical conditions, the hypothetical conditions comprising: (a) the gun barrel is communicated with the shaft after perforation and forms an annular high-pressure gas cavity, (b) the pressure at each position in the shaft is the same, (c) the gas and perforating fluid interface is in the same horizontal plane, (d) the moving direction of the gas and perforating fluid in the shaft is one-dimensional, (e) the perforating fluid pressure wave is transmitted in two directions of upward and downward by taking the perforating gun as the center; (2) and establishing a cylindrical coordinate system, taking the left shaft of the shaft as a y-axis, and taking the shaft downwards as a positive axis.
In a possible embodiment mode, a one-dimensional model of a pressure field of a shaft of a tubing section during perforation is analyzed, and a control equation set of motion interaction of detonation gas and perforating fluid of perforation of a packing section is established, wherein the control equation set comprises the following steps: according to a one-dimensional model of a pressure field of a shaft of an oil pipe section during perforation, the mass increment of a dt time perforating fluid infinitesimal body dy is considered as the difference between the outflow quantity and the inflow quantity according to a mass conservation law, and a continuity equation is as follows:
where ρ isw(y, t) is the density of the perforating fluid, sw(y, t) is the cross-sectional area of the wellbore, vw(y, t) is the flow velocity of the perforating fluid.
Assuming that the relationship between the circumferential tensile stress and strain in the wellbore due to pressure increase is:
in fact, the resulting circumferential strain Δ dw/doVery small, then:
wherein d iswFor wellbore diameter, subscript 0 is the initial value (same below); h iswThe thickness of the well wall; ewIs the wellbore elastic modulus;
the amount of density change can be related to the pressure increase by taking into account the elastic properties of the wellbore and the fluid:
wherein eta iswFor a shaftVolume index of the fluid.
The following equation can be derived by taking the derivative of the density and cross-sectional area:
and (3) finishing the equations (1) to (6) to obtain a perforating fluid motion continuity equation:
wherein, Pw(y, t) is the perforating fluid pressure,
is the velocity of propagation of the shock wave in the wellbore.
For compressible fluids in the y direction in the wellbore, considering its own frictional resistance and gravity, according to newtonian's second law, its one-dimensional momentum equation can be expressed as:
wherein, muwIs the friction coefficient between the shaft liquid and the wall surface of the shaft.
Finally, the control equation set of the movement interaction of the detonation gas of the perforation of the packing section and the perforation liquid is obtained through finishing:
and (3) arranging and converting a control equation set of the motion interaction of the detonation gas and the perforating fluid of the packer section into a full differential equation:
due to vw，PwBoth as a function of time and space, so that the derivation of time yields:
if it is
In combination with equations (10) - (12), a full differential equation corresponding to the control equation set can be obtained:
wherein,
in a possible embodiment mode, the full differential equation set is solved to obtain a perforation fluid pressure wave propagation motion equation set, wherein the solving of the full differential equation to obtain the perforation fluid pressure wave propagation motion equation set is as follows:
in the equation set, the forward propagation velocity and the backward propagation velocity of the shock wave in the perforating fluid are respectively vw+cwAnd vw-cw. Because the detonation gas pressure generated by the perforation is extremely high, the fluid where the pressure wave arrives is compressed, the volume of the detonation gas is increased along with the continuous explosion of the subsequent perforating bullet, and the formed perforation pressure wave can reciprocate back and forth for many times in the shaft. Followed byThe perforation shock wave gradually shows an attenuation trend along with the dissipation of explosion energy and the well wall friction resistance, and under the condition that the upper part of the perforation liquid is not blocked, the perforation liquid is firstly compressed under the action of detonation gas and then moves upwards.
In a possible embodiment mode, the method comprises the following steps of obtaining a perforating fluid compression velocity equation by analyzing the volume compressibility of the perforating fluid based on a motion equation set of the perforating fluid under the action of detonation gas by using an underwater explosion theory, and obtaining an upward motion equation of the perforating fluid according to a hydraulic theory and Newton's second law, wherein the motion equation comprises the following steps: according to the theory of underwater explosion, the perforating fluid is compressible under ultra-high pressure conditions, and the pressure difference acting on the perforating fluid microelements is used for compressing the volume of the perforating fluid, the pressure difference can be expressed as:
ΔPw＝P(t)-[Ps+ρwg(y-y0-cwt)]； (15)
wherein, PsIs standard atmospheric pressure, Pa; p (t) is the perforating explosive gas pressure, Pa;
the perforation fluid volume compression can be expressed as:
wherein psi is the perforation liquid volume compression coefficient; dVwCompressed volume of perforating fluid, m3； VwIs the initial volume of the perforating fluid, which can be expressed as Vw＝cw·sw·dt；m3。
The perforation fluid compression motion velocity equation can be obtained by carrying out the reduction on the formulas (14), (15) and (16) without considering the change of the cross section in the fluid compression process:
wherein v isyThe compression velocity of the perforating fluid is m/s.
After the perforating fluid is compressed, the subsequent perforation deflagration gas continuously pushes the compressed perforating fluid to move upwards, and according to the theory of hydraulics and Newton's second law, a one-dimensional momentum equation (8) can further obtain an upward movement equation of the perforating fluid:
in a possible embodiment mode, after the movement condition of the perforating fluid is analyzed, the movement equation of the perforating fluid in the compression section and the movement equation of the ascending section are obtained, and then the movement distance of the perforating fluid under the action of detonation gas is obtained. And obtaining the compressive movement velocity of the perforating fluid according to the perforating fluid compressive movement velocity equation, and obtaining the upward movement velocity of the perforating fluid according to the upward movement equation of the perforating fluid. The step of predicting the movement space size of the perforating fluid of the packing section according to the compression movement speed of the perforating fluid and the upward movement speed of the perforating fluid comprises the following steps: assuming that under the detonation gas, the compression movement time of the perforating fluid is t1, and the ascending movement time is t2, the size of the perforating fluid movement space X is as follows:
X＝vyt1+vwt2； (19)
x is the movement space distance of the perforating fluid, and X is the movement space size of the perforating fluid of the seal segment.
The method for predicting the movement space of the perforating fluid of the packer section provided by the invention is explained in a specific embodiment.
Example well 1 operating parameters were: the well depth is 1295m, the formation pressure is 12MPa, and the length of the artificial bottom hole pocket is 36.06 m; the model of the perforating gun is 178, the outer diameter is 177.8mm, the wall thickness is 12.65mm, and the yield limit is 550 MPa; the gun is 9m long, the hole density is 40 holes per meter, the total number of perforating bullets in a perforating section reaches 336, the charge type is HMX, the charge amount is 40g, and the perforating bullets adopt a sequential detonation mode; the sleeve is made of N80 steel grade, and has an outer diameter of 244.4mm, an inner diameter of 220.5mm and a yield limit of 460.2 MPa; the oil pipe is made of N80 steel grade, the outer diameter is 73.02mm, the inner diameter is 62mm, the yield limit is 536MPa, and the total length of the oil pipe below the packer is 19.14 m; the packer is of an RTTS type, and the working pressure is 69 MPa; the density of the perforating fluid is 1.03g/cm3, and the initial pressure of a shaft is 10 MPa; the numerical value is substituted into the established numerical calculation model of the perforating fluid motion equation to be calculated, and the time is used as an abscissa, and the compression speed and the rising speed are respectively used as an ordinate to be plotted, so that the perforating fluid speed and time change rule shown in fig. 4 and 5 can be obtained, wherein fig. 4 is a change curve of the perforating fluid compression speed along with time, and fig. 5 is a change curve of the perforating fluid rising speed along with time, and specifically, the curve characteristics comprise the following two points:
firstly, under the action of perforating detonation gas, the compression speed of perforating fluid is sharply increased and reaches a peak value; second, the rate of perforation fluid rise increases linearly with time.
In the example well 1, assuming no upper seal, the total distance of movement of the perforating detonation gas to push the perforating fluid is 31.62m, and in the example well the tubing below the packer is only 19.14m, which does not provide enough space for the perforating fluid to move.
In summary, the method for predicting the space size provided by the packer for the movement of the perforating fluid can be used as a theoretical basis of perforation design and is a reference for actual perforation operation.
The invention provides a prediction method of the movement space size of packer section perforating fluid, which is based on the physical process analysis in an oil pipe section shaft during perforating, carries out condition hypothesis and establishes a one-dimensional model of a pressure field in the oil pipe section shaft during perforating; establishing a perforating fluid motion equation set according to the interaction between the perforating detonation gas and the perforating fluid; the compressibility of the perforating fluid under the condition of ultrahigh pressure is considered, and a perforating fluid volume compression coefficient is introduced to obtain a compression velocity equation of the perforating fluid; and further obtaining a perforating fluid motion equation according to a hydraulics theory and a Newton's second law. In order to ensure the accuracy of the calculation result, the change rule of the perforating fluid compression speed along with time is obtained by adopting the data of the example well 1, and the prediction of the movement space size of the perforating fluid at the packing section is realized.
The prediction method for predicting the movement space of the perforating fluid at the packing section has the advantages that:
(1) under the assumed condition, a one-dimensional model of a pressure field of a shaft of an oil pipe section during perforation is established, so that the motion rule of perforating fluid in the shaft can be accurately described, and a strong function is displayed;
(2) a motion control equation set of perforating fluid in a shaft of the oil pipe section is established, and the numerical calculation problem of the motion of the perforating fluid is solved;
(3) firstly, the control equation of partial differential is simplified into a full differential form, so that the difficulty of numerical calculation is reduced;
(4) the compressibility of the perforating fluid under the condition of ultrahigh pressure is considered, and the integral compression coefficient of the perforating fluid is introduced, so that the problem of calculation of the speed of the perforating fluid during perforating is solved;
(5) and introducing field data of the example well 1, substituting the field data into an equation and obtaining the motion condition of the perforating fluid under the perforating impact effect. The method for calculating the movement space size of the perforating fluid in the packing section through physical modeling and numerical value can not only ensure the prediction precision of the space size, but also obtain the change rule of the movement speed of the perforating fluid along with time, can provide more useful information and provide theoretical basis for scientific perforation design.
While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include such modifications and variations.
Claims (7)
1. A method for predicting the movement space size of perforating fluid in a packing section is characterized by comprising the following steps:
establishing a one-dimensional model of the pressure field of the shaft of the oil pipe section during perforation by analyzing the physical process of the pressure field of the shaft of the oil pipe section and assuming conditions;
analyzing a one-dimensional model of a pressure field of a shaft of the oil pipe section during perforation, and establishing a control equation set of motion interaction of detonation gas and perforating fluid of the perforating section, wherein the control equation set comprises a relation equation set of pressure, speed, sectional area of the shaft and density along with time and position change;
converting the control equation set into a full differential equation set;
resolving the full differential equation set to obtain a perforating fluid pressure wave propagation motion equation set, and analyzing to obtain a motion equation set of the perforating fluid under the action of detonation gas after analyzing the change condition of the pressure wave generated by the detonation gas in the packing section;
based on the motion equation set of the perforating fluid under the action of detonation gas, obtaining a perforating fluid compression velocity equation by analyzing the volume compressibility of the perforating fluid by using an underwater explosion theory, and obtaining an upward motion equation of the perforating fluid according to a hydraulic theory and a Newton's second law;
calculating the compression movement speed of the perforating fluid when the perforating fluid is compressed according to a perforating fluid compression speed equation, and calculating the upward movement speed of the perforating fluid after the perforating fluid is decompressed according to a perforating fluid upward movement equation;
and predicting the movement space size of the perforating fluid of the packing section according to the compression movement speed of the perforating fluid and the upward movement speed of the perforating fluid.
2. The prediction method of claim 1, wherein the establishing of the one-dimensional model of the wellbore pressure field of the tubing section at the time of perforation through the physical process analysis and condition assumption of the wellbore pressure field of the tubing section comprises:
determining hypothetical conditions, the hypothetical conditions comprising: (a) the gun barrel is communicated with the shaft after perforation and forms an annular high-pressure gas cavity, (b) the pressure at each position in the shaft is the same, (c) the gas and perforating fluid interface is in the same horizontal plane, (d) the moving direction of the gas and perforating fluid in the shaft is one-dimensional, (e) the perforating fluid pressure wave is transmitted in two directions of upward and downward by taking the perforating gun as the center;
and establishing a cylindrical coordinate system, taking the left shaft of the shaft as a y-axis, and taking the shaft downwards as a positive axis.
3. The prediction method of claim 2, wherein the one-dimensional model of the pressure field of the shaft of the oil pipe section during perforation is analyzed, and a control equation set of the motion interaction between the detonation gas and the perforating fluid of the perforation of the packing section is established, and comprises the following steps:
according to the one-dimensional model of the pressure field of the oil pipe section shaft during perforation, the mass increment of a dt time perforating fluid infinitesimal body dy is considered as the difference between the outflow quantity and the inflow quantity according to the mass conservation law, and the continuity equation is as follows:
where ρ isw(y, t) is the density of the perforating fluid, sw(y, t) is the cross-sectional area of the wellbore, vw(y, t) is the flow velocity of the perforating fluid;
the relationship between the circumferential tensile stress and the strain caused by the pressure increment in the well bore is as follows:
in fact, the circumferential strain Δ dw/do produced is very small, then:
wherein d iswIs the diameter of the wellbore, subscript 0 is the initial value; h iswThe thickness of the well wall; ewIs the wellbore elastic modulus;
the amount of density change can be related to the pressure increase by taking into account the elastic properties of the wellbore and the fluid:
wherein eta iswIs a volume index of the wellbore fluid;
the following equation can be derived by taking the derivative of the density and cross-sectional area:
and (3) finishing the equation to obtain a perforating fluid motion continuity equation:
wherein, Pw(y, t) is the perforating fluid pressure,
is the velocity of propagation of the shock wave in the wellbore;
for compressible fluids in the y direction in the wellbore, considering its own frictional resistance and gravity, according to newtonian's second law, its one-dimensional momentum equation can be expressed as:
wherein, muwThe friction coefficient of the shaft liquid and the wall surface of the shaft is shown;
finally, the control equation set of the movement interaction of the detonation gas of the perforation of the packing section and the perforation liquid is obtained through finishing:
4. the prediction method of claim 3, wherein converting the system of governing equations into a system of fully differential equations comprises:
converting a control equation set of the motion interaction of the detonation gas of the perforation of the packing section and the perforating fluid into an ordinary differential equation:
due to vw，PwBoth as a function of time and space, so that the derivation of time yields:
if there is
Then the full differential equation can be obtained as:
wherein,
5. the prediction method of claim 4, wherein the solving the system of fully differential equations to obtain the system of equations for perforating fluid pressure wave propagation motion comprises:
solving the full differential equation to obtain a system of perforation liquid pressure wave propagation motion equations as follows:
wherein the forward and backward propagation velocities of the shock wave in the perforating fluid are vw+cwAnd vw-cw。
6. The prediction method of claim 5, wherein the obtaining of the perforation fluid compression velocity equation by analyzing the volume compressibility of the perforation fluid based on the motion equation set of the perforation fluid under the action of the detonation gas by using the underwater explosion theory, and the obtaining of the upward motion equation of the perforation fluid according to the hydraulic theory and Newton's second law comprise:
according to the theory of underwater explosion, the perforating fluid is compressible under ultra-high pressure conditions, and the pressure difference acting on the perforating fluid microelements is used for compressing the volume of the perforating fluid, the pressure difference can be expressed as:
ΔPw＝P(t)-[Ps+ρwg(y-y0-cwt)]；
wherein, PsIs standard atmospheric pressure, Pa; p (t) is the perforating explosive gas pressure, Pa;
the perforation fluid volume compression can be expressed as:
wherein psi is the perforation liquid volume compression coefficient; dVwCompressed volume of perforating fluid, m3；VwIs the initial volume of the perforating fluid, which can be expressed as Vw＝cw·sw·dt；m3；
And (3) the change of the cross section in the fluid compression process is not considered, and the perforation fluid compression motion velocity equation can be obtained through finishing simplification:
wherein v isyThe compression speed of the perforating fluid is m/s;
after the perforating fluid is compressed, the subsequent perforation deflagration gas continuously pushes the compressed perforating fluid to move upwards, and according to the theory of hydraulics and Newton's second law, a one-dimensional momentum equation can further obtain an upward movement equation of the perforating fluid:
7. the prediction method of claim 6, wherein the space size of the perforating fluid moving space of the packer section is predicted according to the compression moving speed of the perforating fluid and the upward moving speed of the perforating fluid:
assuming that under the detonation gas, the compression time of the perforating fluid is t1, and the ascending movement time is t2, the size of the perforating fluid movement space X is as follows:
X＝vyt1+vwt2；
and X is the movement space distance of the perforating fluid.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105484687A (en) * | 2015-11-27 | 2016-04-13 | 中国海洋石油总公司 | Perforation transient well fluid pressure prediction method |
| CN105885811A (en) * | 2016-05-04 | 2016-08-24 | 长江大学 | High-strength high-thixotropy horizontal well annular chemical packer material and preparation process thereof |
| CN108625828A (en) * | 2018-03-28 | 2018-10-09 | 中国石油大学(北京) | Predict the method and device of perforation blast load output size |
| CN108868748A (en) * | 2018-04-28 | 2018-11-23 | 中国石油化工股份有限公司江汉油田分公司石油工程技术研究院 | A kind of calculation method of shale gas horizontal well refracturing crack cracking pressure |
| US20190292884A1 (en) * | 2018-03-21 | 2019-09-26 | ResFrac Corporation | Systems and methods for hydraulic fracture and reservoir simulation |
-
2021
- 2021-02-07 CN CN202110165857.9A patent/CN113033113B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105484687A (en) * | 2015-11-27 | 2016-04-13 | 中国海洋石油总公司 | Perforation transient well fluid pressure prediction method |
| CN105885811A (en) * | 2016-05-04 | 2016-08-24 | 长江大学 | High-strength high-thixotropy horizontal well annular chemical packer material and preparation process thereof |
| US20190292884A1 (en) * | 2018-03-21 | 2019-09-26 | ResFrac Corporation | Systems and methods for hydraulic fracture and reservoir simulation |
| CN108625828A (en) * | 2018-03-28 | 2018-10-09 | 中国石油大学(北京) | Predict the method and device of perforation blast load output size |
| CN108868748A (en) * | 2018-04-28 | 2018-11-23 | 中国石油化工股份有限公司江汉油田分公司石油工程技术研究院 | A kind of calculation method of shale gas horizontal well refracturing crack cracking pressure |
Non-Patent Citations (4)
| Title |
|---|
| QIAO DENG 等: "Analysis of impact load on tubing and shock absorption during perforating", 《DE GRUYTER》 * |
| QIAO DENG 等: "Effects of perforation fluid movement on downhole packer with shock loads", 《JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING 195》 * |
| 李柏杨: "射孔冲击载荷下封隔器中心管强度安全性分析", 《中国优秀博硕士学位论文全文数据库(硕士) 工程科技Ⅰ辑》 * |
| 赵旭 等: "复合射孔上部压井液运动理论模型研究", 《钻井液与完井液》 * |
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