Method and system for calculating opening number of eyelets, computer equipment and medium

Abstract

The invention provides a method and system for calculating the opening number of eyelets, computer equipment and a medium. The method comprises the steps that a seam pressure calculation equation is obtained through coupling; carrying out two adjacent discharge capacities and two seam pressures, and carrying out coupling to obtain a calculation equation of the opening number of the eyelets; according to the obtained hole opening number calculation equation, the number N1 of opened holes in the pump stopping stage before the temporary plugging material is added, the number N2 of remaining opened holes in the pump starting stage after the temporary plugging material is added and the number N3 of newly opened holes in the pump stopping stage after the temporary plugging material is added are calculated in the fracturing construction process of each section; according to the hole number N1 and the hole number N2, the hole number N4 plugged by the temporary plugging material is obtained; and according to the hole number N3 and the hole number N4, the total hole opening number N5 after construction is completed is obtained. The system comprises a data collection module, a data processing module and a digital display module which are connected in sequence. The method has the beneficial effect that the method can be popularized and applied on a large scale.

Description

Technical Field

[0001] This invention relates to the field of petroleum engineering, and more specifically, to a method, system, computer equipment, and medium for calculating the number of open boreholes. Background Technology

[0002] Inter-well cluster temporary plugging and diversion fracturing technology is a key means to achieve efficient shale gas extraction. This technology mainly involves sealing opened perforations with temporary plugging materials, thereby forcing subsequent injected fluid to divert into unopened perforations, creating new fractures, and ultimately increasing fracture complexity to achieve full and uniform stimulation of the horizontal well section. Calculating the number of perforations opened before and after temporary plugging is an important way to evaluate the effectiveness of the temporary plugging.

[0003] Currently, the number of open perforations after temporary plugging is mainly analyzed using downhole television imaging technology. The main principle of this technology is that after the temporary plugging fracturing operation is completed, a downhole television is installed in the wellbore to photograph the open perforations, and the results are ultimately presented on the surface as images. This method has the advantage of directly observing the shape, size, and number of open perforations at different locations, but it also has disadvantages such as high cost, long processing time, and difficulty in large-scale application at fracturing sites. Furthermore, existing models for calculating the number of open perforations based on fracturing operation curves do not consider the effect of perforation erosion and are difficult to calculate the number of perforations sealed after the addition of temporary plugging material, leading to underestimated final results. To address the shortcomings of existing methods, this invention proposes a method for calculating the number of open perforations in shale gas pressure fracturing, based on fracturing operation curves obtained in real time during the fracturing process and considering the perforation pattern effect.

[0004] A Chinese invention patent application with application number "CN202211318196.X" and titled "Method, Equipment, and Medium for Temporary Plugging of Multi-Cluster Fracturing in Atmospheric Pressure Shale Gas" discloses a method for calculating the total amount of fluid to be injected before plunging a plunging ball based on the number of opened perforations and the fluid volume of a single cluster fracture, thus determining the timing of plunging. The steps for calculating the number of opened perforations include: conducting downhole core mechanical analysis experiments to determine the number of perforations in each perforation section; and calculating the number of opened perforations after injecting pre-fracturing fluid. However, this process does not consider the influence of perforation erosion and other factors during the calculation of the number of opened perforations, which may lead to deviations in the temporary plugging effect. Summary of the Invention

[0005] The purpose of this invention is to address at least one of the aforementioned shortcomings of the prior art. For example, one objective of this invention is to provide a more reliable method for calculating the number of open fracturing orifices. Another objective of this invention is to provide a highly operable system for calculating the number of open fracturing orifices in shale gas.

[0006] To achieve the above objectives, the present invention provides a method for calculating the number of shale gas fracturing orifices to be opened. This method may include the following steps: S1, coupling the calculation equations for wellhead pressure, orifice friction, orifice diameter, orifice flow coefficient, wellbore friction, and wellbore hydrostatic pressure to obtain the orifice pressure calculation equation; S2, using a certain step displacement, performing two adjacent stepped stop displacement or stepped increase displacement operations, ensuring the two orifice pressures are equal, and coupling the orifice pressure calculation equations under the two adjacent displacement operations to obtain the orifice pressure calculation equation. S3. Using the calculation equation for the number of openings in step S2, calculate the number of openings N1 during the pump stop stage before the addition of temporary plugging material, the remaining number of openings N2 during the pump start stage after the addition of temporary plugging material, and the number of newly openings N3 during the pump stop stage after the addition of temporary plugging material in each stage of fracturing construction; S4. Based on the number of openings N1 and N2, obtain the number of openings N4 sealed by temporary plugging material; S5. Based on the number of openings N3 and N4, obtain the total number of openings N5 after the construction is completed.

[0007] According to one or more exemplary embodiments of the present invention, the equation for calculating the number of opening holes can be as shown in equation (1):

[0008]

[0009] Where N is the number of open orifices, dimensionless; ρ is the density of the fracturing fluid, kg / m³. 3 ; q1 is the initial fracturing fluid injection volume, m 3 / min; q2 is the fracturing fluid injection rate for the second flush, m 3 / min; D is the casing diameter, m; d i P is the initial equivalent diameter of the orifice, in meters; M is the sand feed rate into the orifice, in kilograms; P k1 P represents the wellhead pressure for the first discharge, in MPa. k2 The wellhead pressure for the second discharge is in MPa.

[0010] According to one or more exemplary embodiments of the present invention, the seam pressure calculation equation is as shown in equation (2):

[0011]

[0012] Among them, P w P represents the seam pressure, measured in MPa. k ρ is the wellhead pressure, MPa; ρ is the fracturing fluid density, kg / m³ 3 ; q represents the fracturing fluid injection rate, m 3 / min; f is the friction coefficient of the fracturing fluid, dimensionless; L is the casing length, m; D is the casing diameter, m; g is the gravitational acceleration, 9.8 N / kg; h is the vertical depth of the wellbore, m; N is the number of open orifices, dimensionless; d i M is the initial equivalent diameter of the orifice, in meters; M is the amount of sand fed into the orifice, in kilograms.

[0013] According to one or more exemplary embodiments of one aspect of the present invention, during each stage of fracturing construction, in the pump shutdown stage before the addition of temporary plugging material, the pump can be shut down using two adjacent shutdown rates to obtain the wellhead pressure under two adjacent different discharge rates; in the pump start-up stage after the addition of temporary plugging material, the pump can be started up using two adjacent step-increase discharge rates to obtain the wellhead pressure under two adjacent different discharge rates; in the pump shutdown stage after the addition of temporary plugging material, the pump can be shut down using two adjacent step-decrease discharge rates to obtain the wellhead pressure under two adjacent different discharge rates.

[0014] According to one or more exemplary embodiments of one aspect of the present invention, the seam pressure under the two adjacent discharge rates may be equal, as shown in equation (3):

[0015] P W1 =P W2 (3)

[0016] Among them, P w1 The seam pressure for the first discharge, MPa, P w2 The seam pressure for the first discharge is measured in MPa.

[0017] According to one or more exemplary embodiments of one aspect of the present invention, the displacement of a certain step size in step S2 may include 1 to 2 m. 3 / min.

[0018] In another aspect, the present invention provides a system for calculating the number of shale gas fracturing orifices opened. The system may include a data collection module, a data processing module, and a digital display module connected in sequence. The data collection module is configured to collect construction data and transmit the collected data to the data processing module. The data processing module uses an orifice opening calculation equation to calculate, based on the construction data transmitted by the data collection module, the number of orifices opened (N1) before the pump is stopped (before the addition of temporary plugging material), the remaining number of orifices opened (N2) after the pump is started (after the addition of temporary plugging material), the number of newly opened orifices (N3) after the pump is stopped (after the addition of temporary plugging material), the number of orifices sealed with temporary plugging material (N4), and the total number of orifices opened (N5) after the fracturing operation. The digital display module is configured to receive and display the data results calculated by the data processing module.

[0019] According to one or more exemplary embodiments of another aspect of the present invention, the construction data collected by the data collection module may include fracturing fluid injection rate, fracturing fluid density, number of open orifices, orifice equivalent diameter, orifice flow coefficient, initial orifice equivalent diameter, orifice sand inlet rate, fracturing fluid friction coefficient, casing length, casing diameter, and wellbore vertical depth.

[0020] In another aspect, the present invention provides a computer device, which may include: a processor; and a memory storing a computer program that, when executed by the processor, implements the method for calculating the number of shale gas fracturing orifices to be opened as described in the exemplary embodiments above.

[0021] In another aspect, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a method for calculating the number of shale gas fracturing orifices to be opened as described in the exemplary embodiments above.

[0022] Compared with the prior art, the beneficial effects of the present invention include at least one of the following:

[0023] (1) The method for calculating the number of open holes provided by the present invention has a short calculation time and can be widely promoted and applied.

[0024] (2) The computing system provided by the present invention has a simple structure and is easy to implement. Attached Figure Description

[0025] The above and other objects and / or features of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0026] Figure 1 A schematic diagram of the fracturing operation curve of well A in Example 1 of the present invention is shown;

[0027] Figure 2 The diagram shows a comparison between the calculation method of this invention and the downhole television results for Well A in Example 1 of this invention. Detailed Implementation

[0028] In the following, a method, system, computer device, and medium for calculating the number of open apertures according to the present invention will be described in detail with reference to exemplary embodiments.

[0029] The terms “S1”, “S2”, “S3”, “S4”, “S5”, “S201”, “S202”, etc. used in this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0030] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the term "connected" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] First exemplary embodiment

[0032] This exemplary embodiment provides a method for calculating the number of fracturing orifices to be opened in shale gas.

[0033] In this exemplary embodiment, the method for calculating the number of shale gas fracturing orifices to be opened mainly includes the following steps S1 to S5:

[0034] S1. The calculation equation for joint pressure at the wellhead, orifice friction, orifice diameter, orifice flow coefficient, wellbore friction and wellbore hydrostatic pressure is obtained.

[0035] S2. Using a certain step size for the discharge rate, perform two adjacent step stop discharge rates or step increase discharge rates, with the two seam pressures being equal. Couple the seam pressure calculation equations under the two adjacent discharge rates to obtain the calculation equation for the number of opening holes.

[0036] S3. Using the calculation equation for the number of openings in step S2, calculate the number of openings N1 during the pump stop stage before the addition of temporary plugging material, the remaining number of openings N2 during the pump start stage after the addition of the plugging material, and the number of newly openings N3 during the pump stop stage after the addition of the plugging material in each fracturing operation.

[0037] S4. Based on the number of holes N1 and N2, obtain the number of holes N4 sealed by the temporary plugging material.

[0038] S5. Based on the number of holes N3 and the number of holes N4, the total number of holes N5 opened after construction is completed.

[0039] In this exemplary embodiment, the process of obtaining the joint pressure calculation equation by coupling the six calculation equations of wellhead pressure, orifice friction, orifice diameter, orifice flow coefficient, wellbore friction and wellbore hydrostatic pressure in step S1 may include:

[0040] 1) Calculate the wellhead pressure P k :

[0041] P k =P w +P m +P f -P h

[0042] Where: Pk P represents the wellhead pressure, in MPa. w P represents the seam pressure, measured in MPa. m The frictional resistance of the orifice is measured in MPa; P f For wellbore friction, MPa; P h ρ is the hydrostatic pressure, MPa.

[0043] 2) Calculate the hole friction P m :

[0044]

[0045] Where: q is the fracturing fluid injection rate, m 3 / min; ρ is the density of the fracturing fluid, kg / m³ 3 N is the number of open apertures, dimensionless; d is the equivalent diameter of the aperture, in meters; K d The orifice flow coefficient is dimensionless and less than 0.89.

[0046] 3) Based on the relationship between the equivalent diameter of the orifice and the sand feed rate, calculate the equivalent diameter d of the orifice:

[0047] d = d i +2.4*10 -7 M

[0048] Where: d i M is the initial equivalent diameter of the orifice, in meters; M is the amount of sand fed into the orifice, in kilograms.

[0049] 4) Calculate the orifice flow coefficient K based on the relationship between the orifice flow coefficient and the orifice sand inlet rate. d :

[0050] K d =0.56 + 3.64 * 10 -4 M

[0051] Where M is the amount of sand fed into the orifice, in kg.

[0052] 5) Calculate the wellbore friction P f :

[0053]

[0054] Where f is the friction coefficient of the fracturing fluid, which is dimensionless; L is the casing length, in meters; and D is the casing diameter, in meters.

[0055] 6) Calculate the hydrostatic pressure P in the wellbore. h :

[0056] P h =ρgh*10 -6

[0057] Where g is the acceleration due to gravity, 9.8 N / kg; and h is the vertical depth of the wellbore, in meters.

[0058] By combining the calculation equations for wellhead pressure, orifice friction, orifice diameter, orifice flow coefficient, wellbore friction, and wellbore hydrostatic pressure, the calculation equation for slotted pressure is obtained:

[0059]

[0060] Among them, P w P represents the seam pressure, measured in MPa. k ρ is the wellhead pressure, MPa; ρ is the fracturing fluid density, kg / m³ 3 ; q represents the fracturing fluid injection rate, m 3 / min; f is the friction coefficient of the fracturing fluid, dimensionless; L is the casing length, m; D is the casing diameter, m; g is the gravitational acceleration, 9.8 N / kg; h is the vertical depth of the wellbore, m; N is the number of open orifices, dimensionless; d i M is the initial equivalent diameter of the orifice, in meters; M is the amount of sand fed into the orifice, in kilograms.

[0061] In this exemplary embodiment, step S2, the process of obtaining the calculation equation for the number of openings by coupling the calculation equations for the slit pressure under two adjacent discharge rates, may include:

[0062] S201. Calculate the seam pressure under two different displacement rates. The equation for calculating the seam pressure under the first displacement rate is as follows:

[0063]

[0064] Among them, P w1 The seam pressure under the first discharge rate, MPa; P k1 q1 represents the wellhead pressure at the first discharge, in MPa; q1 represents the first discharge volume, in meters. 3 / min.

[0065] Seam pressure under the second displacement:

[0066]

[0067] Among them, P w2 The seam pressure under the first discharge rate, MPa; P k2 q1 represents the wellhead pressure at the first discharge, in MPa; q2 represents the first discharge volume, in meters. 3 / min.

[0068] S202. Perform two stepped stop-discharge operations or two stepped increase-discharge operations. Since the difference between the two adjacent discharge operations is small, the joint pressure can be considered equal in both operations.

[0069] P W1 =PW2 .

[0070] Therefore, the calculation equation for the number of opening holes can be obtained by coupling the calculation equations for the seam pressure under two different discharge rates:

[0071]

[0072] N is the number of open orifices, dimensionless; ρ is the density of the fracturing fluid, kg / m³. 3 ; q1 is the initial fracturing fluid injection volume, m 3 / min; q2 is the fracturing fluid injection rate for the second flush, m 3 / min; D is the casing diameter, m; d i P is the initial equivalent diameter of the orifice, in meters; M is the sand feed rate into the orifice, in kilograms; P k1 P represents the wellhead pressure for the first discharge, in MPa. k2 The wellhead pressure for the second discharge is in MPa.

[0073] In this exemplary embodiment, in step S3, calculating the number of open orifices N1 during the pump shutdown stage before the addition of temporary plugging material in each fracturing operation may include: during the pump shutdown stage before the addition of temporary plugging material in each fracturing operation, using a discharge rate of 1-2 m³ / s. 3 / min step size, for example, 1m 3 / min, 1.4m 3 / min or 1.7m 3 The pump was stopped by gradually reducing the discharge rate by a certain amount per minute, and the wellhead pressure at two adjacent discharge rates was obtained. At the same time, the number of open orifices N1 before the addition of the temporary plugging material was calculated using the orifice opening calculation equation obtained in step S2.

[0074] In this exemplary embodiment, in step S3, adding the remaining number N2 of open orifices in the post-pump start-up stage may include: adding temporary plugging material in the post-pump start-up stage during each fracturing operation, using a discharge rate of 1-2 m³ / s. 3 / min step size, for example, 1m 3 / min, 1.4m 3 / min or 1.7m 3 The pump is started using a stepped increase in discharge rate ( / min), and the wellhead pressure is obtained at two adjacent discharge rates of different values. The number of remaining open wells, N2, is calculated using the formula for calculating the number of wells opened after the addition of temporary plugging material, based on the wellhead opening calculation equation obtained in step S2.

[0075] In this exemplary embodiment, in step S3, the number N3 of newly opened orifices after the pump shutdown phase may include: during each fracturing operation, temporary plugging material is added after the pump shutdown phase, using a discharge rate of 1-2 m³ / s.3 / min step size, for example, 1m 3 / min, 1.4m 3 / min or 1.7m 3 The pump was stopped by gradually reducing the discharge rate by a certain amount per minute, and the wellhead pressure at two adjacent discharge rates was obtained. Using the orifice opening calculation equation obtained in step S2, the number of newly opened orifices N3 after the addition of temporary plugging material was calculated.

[0076] In this exemplary embodiment, in step S4, the number of orifices N4 blocked by the temporary plugging material is obtained based on the number of orifices N1 opened during the pump stop stage before the addition of the temporary plugging material obtained in step S3 and the remaining number of orifices N2 opened during the pump start stage after the addition:

[0077] N4 = N1 - N2.

[0078] In this exemplary embodiment, in step S5, the total number of open holes N5 after construction is completed is obtained based on the number of newly opened holes N3 obtained in step S3 during the pump shutdown phase and the number of holes sealed with temporary plugging material N4 obtained in step S4.

[0079] N5 = N3 + N

[0080] Furthermore, as shown in the formula above, N4 is the difference between N1 (the number of holes opened before the addition of the temporary plugging material) and N2 (the number of holes sealed after the addition of the temporary plugging material). Therefore, the specific process for calculating the total number of holes opened, N5, after construction is completed is as follows:

[0081] N5 = N3 + N1 - N2.

[0082] Second exemplary embodiment

[0083] This exemplary embodiment provides a system for calculating the number of fracturing orifices to be opened in shale gas.

[0084] In this exemplary embodiment, the system for calculating the number of shale gas fracturing orifices opened can implement the method for calculating the number of shale gas fracturing orifices opened as described in the first exemplary embodiment. The system for calculating the number of shale gas fracturing orifices opened may include a data collection module, a data processing module, and a digital display module connected in sequence. The data collection module may be configured to collect construction data and transmit the collected construction data to the data processing module. The data processing module may use an orifice opening quantity calculation equation to calculate, based on the construction data transmitted by the data collection module, the number of orifices opened (N1) before the pump is stopped during the temporary plugging material addition phase, the remaining number of orifices opened (N2) after the pump is started, the number of newly opened orifices (N3) after the pump is stopped, the number of orifices sealed with temporary plugging material (N4), and the total number of orifices opened (N5) after the fracturing operation. The digital display module may be configured to receive the data results calculated by the data processing module.

[0085] In this exemplary embodiment, the construction data collected by the data collection module may include fracturing fluid injection rate, fracturing fluid density, number of open orifices, orifice equivalent diameter, orifice flow coefficient, initial orifice equivalent diameter, orifice sand inlet rate, fracturing fluid friction coefficient, casing length, casing diameter, and wellbore vertical depth.

[0086] Third Exemplary Example

[0087] This exemplary embodiment provides a computer device that may include a processor and a memory, the memory being used to store a computer program that, when executed by the processor, implements a method for calculating the number of shale gas fracturing orifices to be opened as described in the first exemplary embodiment.

[0088] Fourth exemplary embodiment

[0089] This exemplary embodiment provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the method for calculating the number of shale gas fracturing orifices to be opened as described in the first exemplary embodiment above.

[0090] To better understand the above exemplary embodiments, the first exemplary embodiment will be further described below with reference to Example 1.

[0091] Example 1

[0092] Figure 1 A schematic diagram of the fracturing operation curve of well A, an example 1 of the present invention, is shown; Figure 2 A comparison chart of the calculation method of this invention and the downhole television results for Well A in Example 1 of this invention is shown below. Figures 1-2 This describes the method for calculating the number of shale gas fracturing orifices to be opened in Example 1.

[0093] Taking well A in a certain area as an example, the calculation of the number of fracturing orifices to be opened for shale gas includes the following steps:

[0094] (1) Taking the first stage of fracturing as an example, during the fracturing process, before the pump is stopped after the temporary plugging material is added, a pumping rate of 1m³ is used. 3 Pump shutdown is performed using a step-by-step reduction in discharge rate ( / min), and the wellhead pressure is obtained as a function of discharge rate. Figure 1 The schematic diagram of the fracturing operation curve for Well A shown in the figure can be used to observe the change in wellhead pressure with displacement rate. The curve can be used to obtain q1 and P for this stage. k1 q2 and P k2 And the total amount of fracturing fluid added up to the end of this stage. Here, as shown in Table 1, the total amount of fracturing fluid added divided by 1 / 3 of the total number of orifices is the amount of fracturing fluid introduced into the orifice, M. Other experimental parameters include fracturing fluid density ρ, casing diameter D, and initial equivalent diameter of the orifice d. i The fracturing fluid friction coefficient f, casing length L, and total number of perforations are all known and constant parameters in the fracturing scheme, as shown in Table 2. Finally, the number of perforations N1 that were opened before the addition of temporary plugging material was calculated using the perforation opening quantity calculation equation, and the results are shown in Table 3.

[0095] Table 1. Displacement, pressure, and sand injection rate at different stages of the first stage of fracturing in Well A.

[0096]

[0097] Table 2A shows the parameters required to calculate the number of orifices to be opened after temporary plugging in the first stage of well A.

[0098] <![CDATA[Fracturing fluid density (kg / m 3 )]]> 1050 Fracturing fluid friction coefficient <![CDATA[2.0*10 -13 ]]> Sleeve diameter (m) 0.114 Sleeve length (m) 4505 Initial equivalent diameter of the aperture (m) 0.01 Total number of holes 56

[0099] Table 3A shows the parameters required to calculate the number of orifices to be opened after temporary plugging in the first stage of well A.

[0100] <![CDATA[The number of perforations N1 that have been opened before adding the temporary plugging material]]> 26 <![CDATA[The number of remaining open holes N2 after adding the temporary plugging material]]> 16 <![CDATA[The number of newly opened holes N3 after adding the temporary plugging material]]> 25 <![CDATA[Total number of hole openings N5 after construction is completed]]> 35

[0101] (2) Taking the first stage of fracturing as an example, during the fracturing process, after the temporary plugging material is added and the pump is started, a pumping rate of 1m³ is used. 3 The pump is started using a step-by-step method with a displacement increment of / min, resulting in the following: Figure 1 The schematic diagram of the fracturing operation curve for Well A shown in the figure can be used to observe the change in wellhead pressure with displacement rate. The curve can be used to obtain q1 and P for this stage. k1 q2 and P k2 And the total amount of sand added up to this stage. Here, as shown in Table 1, the total amount of sand added divided by 1 / 3 of the total number of holes is the amount of sand fed into the holes, M. Finally, the number of remaining open holes, N2, after the addition of the temporary plugging material is calculated using the hole opening number calculation equation, and the results are shown in Table 3.

[0102] (3) Taking the first stage of fracturing as an example, during the fracturing process, after the temporary plugging material is added and the pump is stopped, a discharge rate of 1m³ is adopted. 3 The pump is stopped by stepping down the discharge rate in a step size of / min, resulting in the following: Figure 1 The schematic diagram of the fracturing operation curve for Well A shown in the figure can be used to observe the change in wellhead pressure with displacement rate. The curve can be used to obtain q1 and P for this stage. k1 q2 and P k2 And the total amount of sand added from the start-up to the stop-up phase after the addition of the temporary plugging material. Here, as shown in Table 1, the total amount of sand added divided by 1 / 3 of the total number of orifices is the amount of sand fed into the orifice M (Table 1). Finally, the number of newly opened orifices N3 after the addition of the temporary plugging material is calculated using the orifice opening number calculation equation, and the results are shown in Table 3.

[0103] (4) Taking the first stage of fracturing as an example, the total number of holes N5 opened after the construction was completed was calculated, and the results are shown in Table 3.

[0104] (5) Well A in the actual field has a total of 10 temporary plugging sections. The calculation method for the number of orifices opened after each temporary plugging section is the same as that shown in the first section. The results are shown in Table 3. Figure 2 As shown in the figure, the calculation results of the present invention have a maximum error of 6.1% compared with the results of downhole television observation, indicating that the method in the present invention is reliable in calculating the number of orifices opened after temporary plugging.

[0105] In summary, the advantages of the present invention may include at least one of the following:

[0106] (1) The method for calculating the number of open holes provided by the present invention is based on the fracturing construction curve and takes into account the influence of hole abrasion. It can calculate the number of holes that have been opened before the addition of temporary plugging material, the number of holes that have been sealed after the addition of temporary plugging material, and the number of holes that have been newly opened after the addition of temporary plugging material. The method is correct in principle and the calculation results are more accurate. It can provide a powerful means for evaluating the fracturing effect of temporary plugging in the field.

[0107] (2) The data source for the method of calculating the number of orifices to be opened provided by the present invention is easy to obtain, and it is highly operable and simple to implement for scientific research personnel at the fracturing site;

[0108] (3) The computing system provided by the present invention has accurate calculation results, convenient data acquisition channels, and simple calculation.

[0109] Although a method, system, computer device, and medium for calculating the number of open apertures according to the present invention have been described above in conjunction with exemplary embodiments, those skilled in the art will understand that various modifications and changes can be made to the exemplary embodiments of the present invention without departing from the spirit and scope defined by the claims.

Claims

1. A method for calculating the number of fracturing holes opened in shale gas, characterized in that, The method for calculating the number of shale gas fracturing orifices to be opened includes the following steps: S1. The calculation equation for slotted pressure is obtained by coupling the calculation equations for wellhead pressure, orifice friction, orifice diameter, orifice flow coefficient, wellbore friction and wellbore hydrostatic pressure. S2. Using a certain step size of discharge, perform two adjacent step stop discharge or step increase discharge, with the two seam pressures being equal. Couple the seam pressure calculation equations under the two adjacent discharges to obtain the calculation equation for the number of opening holes. S3. Using the calculation equation for the number of openings in step S2, calculate the number of openings N1 in the pump stop stage before the addition of temporary plugging material, the remaining number of openings N2 in the pump start stage after the addition of the temporary plugging material, and the number of newly openings N3 in the pump stop stage after the addition of the temporary plugging material during each fracturing operation. S4. Based on the number of holes N1 and the number of holes N2, obtain the number of holes N4 sealed by the temporary plugging material; S5. Based on the number of holes N3 and the number of holes N4, the total number of holes N5 opened after construction is completed.

2. The method for calculating the number of shale gas fracturing orifices to be opened according to claim 1, characterized in that, The equation for calculating the number of opening holes is shown in equation (1): Where N is the number of open orifices, dimensionless; ρ is the density of the fracturing fluid, kg / m³. 3 ; q1 is the initial fracturing fluid injection volume, m 3 / min; q2 is the fracturing fluid injection rate for the second flush, m 3 / min; D is the casing diameter, m; d i P is the initial equivalent diameter of the orifice, in meters; M is the sand feed rate into the orifice, in kilograms; P k1 P represents the wellhead pressure for the first discharge, in MPa; k2 The wellhead pressure for the second discharge is in MPa.

3. The method for calculating the number of shale gas fracturing orifices to be opened according to claim 1, characterized in that, The equation for calculating the seam pressure is shown in equation (2): Among them, P w P represents the seam pressure, measured in MPa. k ρ is the wellhead pressure, MPa; ρ is the fracturing fluid density, kg / m³ 3 ; q represents the fracturing fluid injection rate, m 3 / min; f is the friction coefficient of the fracturing fluid, dimensionless; L is the casing length, m; D is the casing diameter, m; g is the gravitational acceleration, 9.8 N / kg; h is the vertical depth of the wellbore, m; N is the number of open orifices, dimensionless; d i M is the initial equivalent diameter of the orifice, in meters; M is the amount of sand fed into the orifice, in kilograms.

4. The method for calculating the number of shale gas fracturing orifices to be opened according to claim 1, characterized in that, During each fracturing operation, before the temporary plugging material is added, the pump is stopped using two consecutive stops with different discharge rates to obtain the wellhead pressure at two different discharge rates. After the temporary plugging material is added, the pump is started using two consecutive steps with increased discharge rates to obtain the wellhead pressure at two different discharge rates. After the temporary plugging material is added, the pump is stopped using two consecutive steps with decreased discharge rates to obtain the wellhead pressure at two different discharge rates.

5. The method for calculating the number of shale gas fracturing orifices to be opened according to claim 3, characterized in that, The seam pressure under the two adjacent discharge rates is equal, as shown in equation (3): P W1 =P W2 (3) Among them, P w1 The seam pressure for the first flush, MPa; P w2 The seam pressure for the first discharge is measured in MPa.

6. The method for calculating the number of shale gas fracturing orifices to be opened according to claim 1, characterized in that, In step S2, a certain step displacement includes 1 to 2 m. 3 / min.

7. A system for calculating the number of fracturing orifices opened in shale gas, characterized in that, The system for calculating the number of shale gas fracturing orifices opened includes a data collection module, a data processing module, and a digital display module connected in sequence. The data collection module is configured to collect construction data and transmit the collected construction data to the data processing module; The data processing module uses an equation to calculate the number of open holes. Based on the construction data transmitted by the data collection module, it calculates the number of open holes N1 before the pump is stopped and then added during each fracturing operation, the remaining number of open holes N2 after the pump is started and then added, the number of newly opened holes N3 after the pump is stopped and then added, the number of holes sealed by the temporary plugging material N4, and the total number of open holes N5 after the operation is completed. The digital display module is configured to receive and display the data results calculated by the data processing module.

8. The system for calculating the number of shale gas fracturing orifices to be opened according to claim 7, characterized in that, The data collection module collects construction data including fracturing fluid injection rate, fracturing fluid density, number of open orifices, orifice equivalent diameter, orifice flow coefficient, initial orifice equivalent diameter, orifice sand inlet rate, fracturing fluid friction coefficient, casing length, casing diameter, and wellbore vertical depth.

9. A computer device, characterized in that, The device includes: processor; and The memory stores a computer program that, when executed by a processor, implements the method for calculating the number of shale gas fracturing orifices to be opened as described in any one of claims 1 to 6.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method for calculating the number of shale gas fracturing orifices as described in any one of claims 1 to 6.

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