Method and device for determining hydraulic fracturing construction parameters

Abstract

The invention provides a method and device for determining hydraulic fracturing construction parameters, and relates to the technical field of new energy development and artificial intelligence. The method comprises the steps that geological parameters of a stratum to be constructed are input into an engineering parameter prediction model, initial engineering parameters are obtained, and the initial engineering parameters represent construction parameters for hydrofracture of the stratum to be constructed; the finite element numerical simulation model is used for conducting hydraulic fracturing numerical simulation on the stratum to be constructed under the initial engineering parameters, and fracture parameters generated through numerical simulation are obtained; based on the fracture parameters and target fracture parameters, the initial engineering parameters are adjusted, updated engineering parameters are obtained, and the target fracture parameters represent ideal parameters of fractures formed after the to-be-constructed stratum is subjected to hydraulic fracturing; and obtaining a target engineering parameter based on the initial engineering parameter and the at least one group of updated engineering parameters in the numerical simulation process.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of new energy development and artificial intelligence technology, in particular to a method and device for determining hydraulic fracturing construction parameters. BACKGROUND

[0002] Hydraulic fracturing is an engineering technology that improves the efficiency of oil and gas, geothermal resource exploitation by injecting high-pressure fluid into the formation to create and expand fractures in the rock. The core principle of hydraulic fracturing is to use fluid pressure to break through the compressive strength of the formation rock and form an artificial fracture network to create a channel for underground resources to flow to the wellbore.

[0003] In related technologies, the construction method of hydraulic fracturing is mainly determined through laboratory experiments and numerical simulation. Numerical simulation is widely used due to its advantages of not being limited by size and saving materials. However, the current numerical simulation method requires repeated trial and error of geological parameters and engineering parameters, and the efficiency of numerical simulation needs to be improved. SUMMARY

[0004] Therefore, the present application provides a method and device for determining hydraulic fracturing construction parameters.

[0005] One aspect of the present application provides a method for determining hydraulic fracturing construction parameters, comprising: inputting geological parameters of a formation to be constructed into an engineering parameter prediction model to obtain initial engineering parameters, the initial engineering parameters representing construction parameters for hydraulic fracturing of the formation to be constructed; performing numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameters using a finite element numerical simulation model to obtain fracture parameters generated by numerical simulation; adjusting the initial engineering parameters based on the fracture parameters and target fracture parameters to obtain updated engineering parameters, the target fracture parameters representing ideal parameters of fractures formed after hydraulic fracturing of the formation to be constructed; and obtaining target engineering parameters based on the initial engineering parameters and at least one set of updated engineering parameters in the numerical simulation process.

[0006] According to an embodiment of the present application, the engineering parameter prediction model includes a first prediction module and a second prediction module; inputting the geological parameters of the formation to be constructed into the engineering parameter prediction model to obtain the initial engineering parameters comprises: inputting the geological parameters of the formation to be constructed into the first prediction module to obtain the target fracture parameters; and inputting the geological parameters and the target fracture parameters into the second prediction module to obtain the initial engineering parameters.

[0007] According to an embodiment of the present application, the second prediction module comprises a first prediction unit and a second prediction unit, and the geological parameters and the target fracture parameters are input into the second module to obtain initial engineering parameters, comprising: inputting the geological parameters and the target fracture parameters into the first prediction unit to obtain initial fracturing fluid parameters, the initial fracturing fluid parameters comprising at least one of fracturing fluid type, fracturing fluid concentration, fracturing fluid displacement, proppant concentration, and fracturing fluid injection time length; inputting the geological parameters, the target fracture parameters, and the initial fracturing fluid parameters into the second prediction unit to obtain initial pressure parameters, the initial pressure parameters comprising at least one of fracture initiation pressure and pump pressure peak value; and obtaining the initial engineering parameters based on the initial fracturing fluid parameters and the initial pressure parameters.

[0008] According to an embodiment of the present application, the initial engineering parameters are adjusted based on the fracture parameters and the target fracture parameters to obtain updated engineering parameters, comprising: based on the fracture parameters, integrating the volume of the fracture generated in the hydraulic fracturing simulation process to obtain a simulation volume of the fracture; and in a case where the simulation volume does not satisfy a target volume, adjusting the initial engineering parameters based on the change trend information of the fracture parameters in the numerical simulation process to obtain the updated engineering parameters; the target volume being determined based on the target fracture parameters.

[0009] According to an embodiment of the present application, the initial engineering parameters are adjusted based on the change trend information of the fracture parameters in the numerical simulation process, comprising: in a case where the change trend information represents that the fracture size tends to be stable, adjusting the initial engineering parameters; and in a case where the change trend information represents that the fracture size tends to increase, not adjusting the initial engineering parameters.

[0010] According to an embodiment of the present application, the fracture parameters comprise fracture width and fracture length; and the change trend information is determined by: based on the fracture width and / or the fracture length at adjacent time points, determining a change rate of the fracture; and based on the change rate of the fracture, determining the change trend information of the fracture.

[0011] According to an embodiment of the present application, the target engineering parameters are obtained based on the initial engineering parameters in the numerical simulation process and at least one set of updated engineering parameters, comprising: continuing to perform hydraulic fracturing simulation on the formation to be constructed under the updated engineering parameters to obtain updated fracture parameters; and in a case where the simulation volume of the fracture satisfies the target volume, obtaining the target engineering parameters based on the initial engineering parameters in the numerical simulation process and at least one set of updated engineering parameters, the simulation volume being determined based on the updated fracture parameters.

[0012] According to an embodiment of the present application, the finite element numerical simulation model is used to perform numerical simulation on hydraulic fracturing of the to-be-constructed stratum under the initial engineering parameters, to obtain fracture parameters generated by the numerical simulation, including: performing format conversion processing on the geological parameters and the initial engineering parameters to obtain geological parameters in a target format and initial engineering parameters in the target format, the target format matching the finite element numerical simulation model; filling the geological parameters in the target format and the initial engineering parameters in the target format into a preset template to obtain a numerical simulation file; inputting the numerical simulation file into the finite element numerical simulation model to perform numerical simulation on hydraulic fracturing of the to-be-constructed stratum under the initial engineering parameters; collecting fracture parameters at a preset time interval during the numerical simulation process to obtain fracture parameters at different time points.

[0013] According to an embodiment of the present application, the engineering parameter prediction model is obtained by training in the following manner: obtaining sample geological parameters, sample fracture parameters and sample engineering parameters; taking the sample geological parameters as input data and the sample fracture parameters as labels to train an initial first prediction module to obtain a trained first prediction module; taking the sample geological parameters and the sample fracture parameters as input data and the sample engineering parameters as labels to train an initial second prediction module to obtain a trained second prediction module; and obtaining the engineering parameter prediction model based on the first prediction module and the second prediction module.

[0014] Another aspect of the present application provides a device for determining hydraulic fracturing construction parameters, including: a first determination module configured to input geological parameters of a to-be-constructed stratum into an engineering parameter prediction model to obtain initial engineering parameters, the initial engineering parameters representing construction parameters for hydraulic fracturing of the to-be-constructed stratum; a simulation module configured to perform numerical simulation on hydraulic fracturing of the to-be-constructed stratum under the initial engineering parameters by using a finite element numerical simulation model to obtain fracture parameters generated by the numerical simulation; an adjustment module configured to adjust the initial engineering parameters based on the fracture parameters and target fracture parameters to obtain updated engineering parameters, the target fracture parameters representing ideal parameters of fractures formed after hydraulic fracturing of the to-be-constructed stratum; and a second determination module configured to obtain target engineering parameters based on the initial engineering parameters and at least one set of updated engineering parameters during the numerical simulation process.

[0015] Another aspect of the present application provides an electronic device, including:

[0016] one or more processors;

[0017] a memory for storing one or more programs,

[0018] wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the method as above.

[0019] Another aspect of the present application provides a computer readable storage medium storing computer executable instructions that, when executed, perform the method as above.

[0020] Another aspect of the present application provides a computer program product comprising computer executable instructions that, when executed, perform the method as above.

[0021] According to the embodiments of the present application, by using the engineering parameter prediction model, the initial engineering parameters for hydraulic fracturing construction can be predicted more accurately according to the geological parameters of the stratum to be constructed. Further, the initial construction parameters are used for numerical simulation of hydraulic fracturing, and the initial construction parameters are dynamically adjusted according to the crack parameters and the target crack parameters, which can greatly reduce the cost of repeated trial and error of numerical simulation, improve the efficiency of numerical simulation, and make the target engineering parameters more in line with the actual construction. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above and other objects, features and advantages of the present application will become more apparent from the following description of the embodiments of the present application taken with reference to the accompanying drawings, in which:

[0023] Figure 1 A flow chart of a method for determining hydraulic fracturing construction parameters according to an embodiment of the present application is schematically shown;

[0024] Figure 2 A flow chart of a method for determining initial engineering parameters according to an embodiment of the present application is schematically shown;

[0025] Figure 3 A flow chart of a method for determining hydraulic fracturing construction parameters according to another embodiment of the present application is schematically shown;

[0026] Figure 4 A block diagram of an apparatus for determining hydraulic fracturing construction parameters according to an embodiment of the present application is schematically shown. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. It is to be understood, however, that the description is merely exemplary and is not intended to limit the scope of the present application. In the following detailed description of the embodiments of the present application, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present application. However, it would be apparent to those skilled in the art that the embodiments of the present application can be practiced without these specific details. In other instances, well-known structures and techniques have not been described in detail in order to avoid obscuring aspects of the present application.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the terms "comprises", "comprising", "includes", "including" and the like are inclusive of the stated features, steps, operations and / or components but are not limited to those features, steps, operations and / or components.

[0029] All terms used herein including technical and scientific terms have the meanings commonly understood by one of ordinary skill in the art unless otherwise specified. It should be noted that the use of terms such as "first", "second" and the like can be used in the description and do not necessarily have an ordinal meaning.

[0030] In the case of using expressions similar to "at least one of A, B, and C, etc.", it should generally be interpreted to include any of them, to include, for example, only A, only B, only C, or a combination of A and B, A and C, B and C, or A and B and C, etc.

[0031] Figure 1 A flowchart of a method for determining hydraulic fracturing construction parameters according to an embodiment of the present application is schematically shown.

[0032] As shown in Figure 1 , the method comprises operations S110-S140.

[0033] In operation S110, geological parameters of a formation to be constructed are input into an engineering parameter prediction model to obtain initial engineering parameters, which represent construction parameters for hydraulic fracturing of the formation to be constructed.

[0034] In operation S120, a finite element numerical simulation model is used to perform numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameters to obtain simulated fracture parameters.

[0035] In operation S130, the initial engineering parameters are adjusted based on the fracture parameters and target fracture parameters to obtain updated engineering parameters, the target fracture parameters representing ideal parameters of fractures formed after hydraulic fracturing of the formation to be constructed.

[0036] In operation S140, target engineering parameters are obtained based on the initial engineering parameters and at least one set of updated engineering parameters in the numerical simulation process.

[0037] In the embodiment, the geological parameters can include geostress parameters, rock mechanics parameters, formation physical property parameters, natural fracture parameters, and the like. The geostress parameters can include, for example, minimum horizontal principal stress, maximum horizontal principal stress, vertical stress, and the like. The rock mechanics parameters can include, for example, Young's modulus, Poisson's ratio, compressive strength, fracture toughness, and the like. The formation physical property parameters can include, for example, depth, permeability, porosity, water saturation, and the like. The natural fracture parameters can include, for example, fracture density, strike, aperture, and the like.

[0038] Exemplarily, the engineering parameter prediction model can be trained based on an eXtreme Gradient Boosting (XGBoost) model, and the application is not limited thereto. The engineering parameter prediction model can also be trained by a neural network model.

[0039] The initial engineering parameters are initial construction parameters for hydraulic fracturing construction, and can include fracturing fluid parameters and pressure parameters.

[0040] In the embodiment, the finite element numerical simulation model is a numerical analysis tool based on the finite element method, which can discretize a continuous formation into a finite number of element combinations, solve physical equations in the process of hydraulic fracturing by using the finite element method, simulate the cracking, expansion and closure process of the cracks according to the solving results, and obtain the crack parameters of the cracks.

[0041] Exemplarily, in the process of numerical simulation of hydraulic fracturing, when the crack parameters under the simulation of the initial construction parameters cannot reach the target crack parameters, the initial construction parameters can be adjusted at least once to obtain updated engineering parameters, and the numerical simulation of hydraulic fracturing is performed under the updated engineering parameters until the crack parameters gradually approach the target crack parameters. Thus, dynamic adjustment of the construction parameters can be realized.

[0042] Exemplarily, if the time for numerical simulation under the initial engineering parameters is a first period, and the time for numerical simulation under the updated engineering parameters is a second period, the target engineering parameters for the entire simulation period can be obtained according to the initial engineering parameters of the first period and the updated engineering parameters of the second period.

[0043] According to the embodiments of the application, the initial engineering parameters for hydraulic fracturing construction can be accurately predicted by using the engineering parameter prediction model according to the geological parameters of the formation to be constructed. Furthermore, the numerical simulation of hydraulic fracturing is performed under the initial construction parameters, and the initial construction parameters are dynamically adjusted according to the crack parameters and the target crack parameters, which can greatly reduce the cost of repeated trial and error of numerical simulation, improve the efficiency of numerical simulation, and make the target engineering parameters more consistent with the actual construction.

[0044] According to an embodiment of the present application, the engineering parameter prediction model comprises a first prediction module and a second prediction module. Inputting the geological parameters of the to-be-constructed stratum into the engineering parameter prediction model to obtain the initial engineering parameters can comprise: inputting the geological parameters of the to-be-constructed stratum into the first prediction module to obtain target fracture parameters; and inputting the geological parameters and the target fracture parameters into the second prediction module to obtain the initial engineering parameters.

[0045] Exemplarily, the first prediction module and the second prediction module can be trained by using the same machine learning model, or can be trained by using different machine learning models. For example, the first prediction module and the second prediction module can be trained by using an XGBoost model, or a neural network model, etc.

[0046] The geological parameters of the to-be-constructed stratum are input into the first prediction module. The first prediction module is used to analyze and process the geological parameters, and to predict the target fracture parameters expected to be achieved under the stratum conditions. For example, the length, width, height, etc. of the fracture are predicted. The target fracture parameters will be one of the inputs of the second prediction module.

[0047] The geological parameters and the target fracture parameters output by the first prediction module are simultaneously input into the second prediction module. The second prediction module comprehensively considers the constraints of the geological parameters on the engineering parameters and the requirements for achieving the target fracture parameters, and obtains the initial engineering parameters for hydraulic fracturing numerical simulation.

[0048] According to an embodiment of the present application, since the stratum geological conditions are different in different regions, the first prediction module can independently analyze and predict various complex geological parameters, and quickly adapt to the fracture prediction requirements under different geological environments. The second prediction module can flexibly adjust the prediction strategy of the engineering parameters based on the results of the first module and the geological parameters, so that the model can give reasonable engineering parameter suggestions under different geological conditions, and the adaptability of the model to various geological conditions is enhanced.

[0049] According to an embodiment of the present application, the second prediction module comprises a first prediction unit and a second prediction unit. Inputting the geological parameters and the target fracture parameters into the second prediction module to obtain the initial engineering parameters can comprise: inputting the geological parameters and the target fracture parameters into the first prediction unit to obtain initial fracturing fluid parameters. The initial fracturing fluid parameters comprise at least one of a fracturing fluid type, a fracturing fluid concentration, a fracturing fluid displacement, a proppant concentration, and a fracturing fluid injection time length. Inputting the geological parameters, the target fracture parameters, and the initial fracturing fluid parameters into the second prediction unit to obtain initial pressure parameters, the initial pressure parameters comprising at least one of a fracture initiation pressure and a pump pressure peak value. Based on the initial fracturing fluid parameters and the initial pressure parameters, the initial engineering parameters are obtained.

[0050] The first prediction unit can use a machine learning model such as XGBoost to learn the complex nonlinear relationships between geological parameters, target fracture parameters, and fracturing fluid parameters based on historical actual engineering data.

[0051] The fracturing fluid type can be slickwater, crosslinked gel, slickwater, linear gel, etc., and different types of fracturing fluids have different chemical properties and physical properties, suitable for different geological parameters. The fracturing fluid concentration can affect the viscosity and performance of the fracturing fluid. The fracturing fluid discharge determines the volume of fracturing fluid injected into the formation per unit time. A larger discharge can quickly form pressure in the formation to promote fracture expansion. Proppants are used to form conductive channels in the fractures and maintain the open state of the fractures. The length of time for fracturing fluid injection needs to be adjusted according to factors such as fracture expansion and formation pressure. Too long injection time can lead to waste of fracturing fluid and excessive damage to the formation; too short injection time may not be able to fully expand the fracture.

[0052] The second prediction unit uses a machine learning model such as XGBoost to learn the complex nonlinear relationships between geological parameters, target fracture parameters, fracturing fluid parameters, and pressure parameters based on historical actual engineering data.

[0053] The fracture initiation pressure is the pressure required to start breaking the formation rock and forming an initial fracture. Accurate fracture initiation pressure prediction can ensure that fracturing operations can be started at the right pressure conditions, avoiding the inability to initiate fractures due to insufficient pressure or excessive damage to the formation due to excessive pressure. The pump pressure peak refers to the peak value of the pump pressure during the fracturing process to maintain the continuous expansion of the fracture.

[0054] Figure 2 The flowchart of the method for determining initial engineering parameters according to an embodiment of the present application is schematically shown.

[0055] The geological parameters 201 are input into the first prediction module M202 to obtain the target fracture parameters 203. The geological parameters 201 and the target fracture parameters 203 are input into the first prediction unit M204 to obtain the initial fracturing fluid parameters 205. The geological parameters 201, the target fracture parameters 203, and the initial fracturing fluid parameters 205 are input into the second prediction unit M206 to obtain the initial pressure parameters 207. According to the initial fracturing fluid parameters 205 and the initial pressure parameters 207, the initial engineering parameters 208 are obtained.

[0056] According to an embodiment of this application, the engineering parameter prediction model is trained as follows: sample geological parameters, sample fracture parameters, and sample engineering parameters are obtained; an initial first prediction module is trained using the sample geological parameters as input data and the sample fracture parameters as labels to obtain a trained first prediction module; an initial second prediction module is trained using the sample geological parameters, sample fracture parameters as input data, and sample engineering parameters as labels to obtain a trained second prediction module; and an engineering parameter prediction model is obtained based on the first and second prediction modules.

[0057] For example, training an initial second prediction module using sample geological parameters and sample fracture parameters as input data, and sample engineering parameters as labels, to obtain a trained second prediction module may include: training an initial first prediction unit using sample geological parameters and sample fracture parameters as input data, and sample fracturing fluid parameters as labels, to obtain a trained first prediction unit; training an initial second prediction unit using sample geological parameters, sample fracture parameters, and sample fracturing fluid parameters as input data, and sample pressure parameters as labels, to obtain a trained second prediction unit; and obtaining a second prediction module based on the first and second prediction units.

[0058] The following uses the XGBoost model as an example to describe the training process of an engineering parameter prediction model.

[0059] First, sample data was collected, including geological parameters, fracture parameters, and engineering parameters. Examples of specific sample data are shown in Table 1.

[0060] Table 1:

[0061]

[0062] Based on preset screening criteria, the sample data is filtered, for example, data with a depth of 2000-3000 meters and a fracturing fluid injection flow rate greater than 0.5 m³ / min and less than 5 m³ / min are selected. The sample data is then normalized and outlier removed as preprocessing to obtain the processed data.

[0063] For the normalization process, please refer to formula (1):

[0064] (1)

[0065] These are the normalized parameters. The parameters collected, The average of all parameters of the same type. The standard deviation is denoted as .

[0066] The abnormal value removal adopts Z-Score method to identify and process data points deviating from the overall distribution, avoiding the interference of measurement errors on the analysis, see formula (2):

[0067] (2)

[0068] is the average of all parameters of the same type parameter, is the average of all parameters of the same type parameter, is the standard deviation. Z is the threshold value of each data point, for example, when the point is identified as an abnormal value and deleted.

[0069] After the above processing, the normalized sample data is obtained, see Table 2.

[0070] Table 2:

[0071]

[0072]

[0073] The above preprocessed sample data is trained by XGBoost machine learning through iteration to obtain multiple weak learners.

[0074] The model of XGBoost is shown in formula (3):

[0075] (3)

[0076] where K is the total number of trees contained in the model, is the kth regression tree, and Xi is the input feature vector, such as sample geological parameters and sample fracture parameters. is the prediction target, such as the initial construction parameter.

[0077] The model can be optimized by the objective function, which contains the loss function and the regularization term, and the objective function Obj is shown in formula (4):

[0078] (4)

[0079] where n is the sample number, i is the sample index, y i is the true label of the ith sample, is the loss function, is the complexity penalty of the kth tree

[0080] The XGBoost model obtains a first prediction module by establishing a mapping function of the geological parameters and the target fracture parameters. The XGBoost model obtains a first prediction unit by establishing a mapping function of the geological parameters, the target fracture parameters and the initial fracturing fluid parameters. The XGBoost model obtains a second prediction unit by establishing a mapping function of the geological parameters, the target fracture parameters, the initial fracturing fluid parameters and the initial pressure parameters.

[0081] According to an embodiment of the present application, the numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameters is performed by using the finite element numerical simulation model, and the fracture parameters generated by the numerical simulation can include: performing format conversion processing on the geological parameters and the initial engineering parameters to obtain geological parameters in a target format and initial engineering parameters in a target format, the target format matching the finite element numerical simulation model; filling the geological parameters in the target format and the initial engineering parameters in the target format into a preset template to obtain a numerical simulation file; inputting the numerical simulation file into the finite element numerical simulation model to perform numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameters; collecting fracture parameters at a preset time interval during the numerical simulation process to obtain fracture parameters at different time points.

[0082] The finite element numerical simulation model usually requires specific formats for input data, such as binary format or text markup format. Through format conversion, the input data can be correctly recognized and read by the finite element numerical simulation model, ensuring the smooth progress of the subsequent simulation process.

[0083] The preset template is a file framework designed for the finite element numerical simulation model, which specifies the organization and structure of data in the file. Filling the converted format parameters according to the preset template can ensure the integrity and standardization of the data.

[0084] The finite element numerical simulation model can simulate and calculate the hydraulic fracturing process by using the finite element method according to the geological parameters and the initial engineering parameters in the file. By discretizing the formation and the fracturing area, the complex continuous problem is converted into a discrete finite element problem, and then the corresponding equation system is solved to simulate the generation and expansion of the fracture during the fracturing process.

[0085] Hydraulic fracturing is a dynamic process, and the fracture will continuously generate and expand over time. By collecting fracture parameters at a preset time interval, the state of the fracture at different stages can be recorded. By collecting fracture parameters such as length, width and height at a set time interval during the simulation process, the evolution of the fracture during the fracturing process can be fully understood.

[0086] According to an embodiment of the present application, adjusting the initial engineering parameter based on the crack parameter and the target crack parameter to obtain the updated engineering parameter can include: based on the crack parameter, integrating the volume of the crack generated in the hydraulic fracturing simulation process to obtain a simulation volume of the crack; in a case where the simulation volume does not satisfy a target volume, adjusting the initial engineering parameter based on the change trend information of the crack parameter in the numerical simulation process to obtain the updated engineering parameter; and the target volume is determined based on the target crack parameter.

[0087] The simulation volume V of the crack f The simulation volume V of the crack can be calculated by formula (5):

[0088] (5)

[0089] wherein, is a crack curved surface domain, is a crack width at a position , and dA is a curved surface microelement area.

[0090] Similarly, the target volume can be calculated in the same way as the simulation volume.

[0091] In a case where the simulation volume satisfies the target volume, it indicates that the crack parameter obtained by performing hydraulic fracturing under the initial engineering parameter can reach the target crack parameter, and the target engineering parameter can be obtained according to the initial engineering parameter.

[0092] If the simulation volume does not satisfy the target volume, it indicates that there is a deviation between the crack volume simulated under the current initial engineering parameter and the target crack parameter. At this time, the initial engineering parameter is adjusted based on the change trend information of the crack parameter in the numerical simulation process. The change trend information of the crack parameter can reflect the development law of the crack in the simulation process, such as crack expansion speed, morphological change, etc. According to these trend information, the initial engineering parameter such as fracturing fluid displacement, pumping pressure, etc. can be adjusted in a targeted manner, so that the crack volume obtained in subsequent simulation is closer to the target volume.

[0093] According to an embodiment of the present application, by calculating the simulation volume and comparing it with the target volume, the gap between the current simulation result and the expected target can be intuitively evaluated. According to the crack parameter change trend to adjust the parameter, the development process of the crack can be better controlled. According to the information such as the speed and direction of crack expansion, the engineering parameter can be adjusted in a timely manner, so that the crack develops according to the expected morphology and scale, improves the controllability of the hydraulic fracturing process, and reduces the construction risk.

[0094] According to an embodiment of the present application, in the case that the simulation volume does not satisfy the target volume, adjusting the initial engineering parameter based on the change trend information of the fracture parameter in the numerical simulation process can include: adjusting the initial engineering parameter in the case that the change trend information represents that the fracture size tends to be stable; and not adjusting the initial engineering parameter in the case that the change trend information represents that the fracture size tends to increase.

[0095] When the change trend information shows that the fracture size tends to be stable, it means that the expansion or change of the fracture has entered a relatively stable stage under the action of the current initial engineering parameter. Continuing to simulate or construct according to the current parameter, the fracture size will not change significantly. At this time, adjusting the initial engineering parameter, such as increasing or decreasing the fracturing fluid discharge, adjusting the pressure, etc., can further promote the expansion of the fracture to achieve the purpose of being closer to the target fracture parameter. For example, if the target fracture length is long, and the current fracture size is stable but does not reach the target length, the initial engineering parameter can be adjusted to stimulate the fracture to continue to expand.

[0096] If the change trend information shows that the fracture size tends to increase, it means that the current initial engineering parameter can effectively promote the expansion of the fracture in the expected direction and degree. In this case, not adjusting the initial engineering parameter and maintaining the current parameter can help the fracture to continue to expand stably until it reaches or approaches the target state. For example, the fracture is growing at a suitable speed, and the morphology also meets the expectation. At this time, maintaining the parameter unchanged can ensure the stability of the simulation or construction process.

[0097] According to an embodiment of the present application, determining whether to adjust the engineering parameter according to the different change trends of the fracture size can more accurately control the development process of the fracture. When the fracture size tends to be stable, timely adjusting the parameter can avoid the fracture from stopping expanding too early and ensure that the fracture can reach the required size of the engineering; and when the fracture size tends to increase, maintaining the parameter unchanged can prevent the fracture from expanding out of control due to excessive adjustment of the parameter and ensure the stability and controllability of the fracture development.

[0098] According to an embodiment of the present application, the fracture parameter includes a fracture width and a fracture length; and the change trend information is determined by: determining a change rate of the fracture based on the fracture width and / or the fracture length at adjacent time points; and determining the change trend information of the fracture based on the change rate of the fracture.

[0099] In the numerical simulation process of hydraulic fracturing, the fracture parameters at different time points can be collected. The change rate of the fracture can be obtained by calculating the ratio of the difference of the fracture width and / or the fracture length at adjacent time points to the time interval.

[0100] If the crack change rate is a positive value and remains relatively stable, it indicates that the crack size is continuously increasing; if the crack change rate gradually decreases and approaches zero, it indicates that the crack size tends to be stable. Through the analysis and judgment of the change rate, it is clear that the crack is in the trend of expansion or stability.

[0101] By calculating the crack width and / or length at adjacent time points to determine the change rate, the subtle changes of the crack during the simulation process can be captured in detail, and the dynamic development of the crack can be more accurately grasped.

[0102] According to the embodiments of the present application, obtaining the target engineering parameter based on the initial engineering parameter in the numerical simulation process and at least one set of updated engineering parameters can include: performing hydraulic fracturing simulation on the formation to be constructed under the updated engineering parameter to obtain updated crack parameters; in the case that the simulation volume of the crack meets the target volume, obtaining the target engineering parameter based on the initial engineering parameter in the numerical simulation process and at least one set of updated engineering parameters, and the simulation volume is determined based on the updated crack parameters.

[0103] When the updated engineering parameter is obtained, hydraulic fracturing simulation is performed on the formation to be constructed under the setting of the updated engineering parameter to obtain updated crack parameters. Based on the updated crack parameters, the simulation volume of the crack is determined by integral calculation or other methods. If the simulation volume meets the target volume, the target engineering parameter is determined from the initial engineering parameter and at least one set of updated engineering parameters used in different time periods in the numerical simulation process at this time.

[0104] For example, in the first period, the initial engineering parameter is used for hydraulic fracturing simulation to meet the target crack parameter. In the second period, the first updated engineering parameter is used for hydraulic fracturing simulation to meet the target crack parameter, and in the third period, the second updated engineering parameter is used for hydraulic fracturing simulation to meet the target crack parameter, etc. Then, the target engineering parameter is obtained according to the initial engineering parameter in the first period, the first updated engineering parameter in the second period and the second updated engineering parameter in the third period.

[0105] According to the embodiments of the present application, the simulation is performed under the updated engineering parameter and the updated crack parameter is obtained, and the process of continuously adjusting and verifying the parameters makes the simulation result more close to the actual situation. Through multiple simulation and parameter adjustment, the generation and expansion of the crack in the hydraulic fracturing process can be more accurately simulated, thereby improving the accuracy of numerical simulation and providing more reliable basis for engineering decision.

[0106] Figure 3 A flowchart of a method for determining hydraulic fracturing construction parameters according to another embodiment of the present application is schematically shown.

[0107] As Figure 3As shown, the geological parameters 310 are input into the engineering parameter prediction model M320 to obtain initial engineering parameters 330. The engineering parameter prediction model M320 comprises a first prediction module M321 and a second prediction module M322.

[0108] Inputting the geological parameters 310 into the engineering parameter prediction model M320 to obtain the initial engineering parameters 330 comprises: inputting the geological parameters 310 into the first prediction module M321 to obtain target fracture parameters 360, and inputting the geological parameters 310 and the target fracture parameters into the second prediction module M322 to obtain the initial engineering parameters 330.

[0109] Inputting the geological parameters 310 and the initial engineering parameters 330 into the finite element numerical simulation model to obtain fracture parameters 350.

[0110] According to the fracture parameters 350, a simulation volume 370 of the fracture is determined, and according to the target fracture parameters 360, a target volume 380 is determined. By comparing the simulation volume 370 and the target volume 380, in a case where the simulation volume 370 does not meet the target volume 380 and the change trend information of the fracture is characterized as tending to be stable, the initial engineering parameters 330 are adjusted to obtain updated engineering parameters 331.

[0111] According to the initial engineering parameters 330 and at least one set of updated engineering parameters 331, target engineering parameters 332 are obtained.

[0112] Figure 4 A block diagram of an apparatus for determining hydraulic fracturing construction parameters according to an embodiment of the present application is schematically shown.

[0113] As Figure 4 The apparatus 400 for determining hydraulic fracturing construction parameters comprises a first determination module 410, a simulation module 420, an adjustment module 430, and a second determination module 440.

[0114] The first determination module 410 is configured to input geological parameters of a formation to be constructed into an engineering parameter prediction model to obtain initial engineering parameters, the initial engineering parameters representing construction parameters for hydraulic fracturing of the formation to be constructed.

[0115] The simulation module 420 is configured to perform numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameters by using a finite element numerical simulation model to obtain fracture parameters generated by the numerical simulation.

[0116] The adjustment module 430 is configured to adjust the initial engineering parameters based on the fracture parameters and target fracture parameters to obtain updated engineering parameters, the target fracture parameters representing ideal parameters of a fracture formed after hydraulic fracturing of the formation to be constructed.

[0117] The second determining module 440 is configured to obtain the target engineering parameter based on the initial engineering parameter and the at least one set of updated engineering parameter in the numerical simulation process.

[0118] According to an embodiment of the present application, the engineering parameter prediction model comprises a first prediction module and a second prediction module. The first determining module can comprise a crack parameter determining submodule and an engineering parameter determining submodule.

[0119] The crack parameter determining submodule is configured to input the geological parameter of the formation to be constructed into the first prediction module to obtain the target crack parameter.

[0120] The engineering parameter determining submodule is configured to input the geological parameter and the target crack parameter into the second prediction module to obtain the initial engineering parameter.

[0121] According to an embodiment of the present application, the second prediction module comprises a first prediction unit and a second prediction unit. The engineering parameter determining submodule can comprise:

[0122] The fracturing fluid parameter determining unit is configured to input the geological parameter and the target crack parameter into the first prediction unit to obtain the initial fracturing fluid parameter. The initial fracturing fluid parameter comprises at least one of a fracturing fluid type, a fracturing fluid concentration, a fracturing fluid displacement, a proppant concentration, and a fracturing fluid injection time length.

[0123] The pressure parameter determining unit is configured to input the geological parameter, the target crack parameter, and the initial fracturing fluid parameter into the second prediction unit to obtain the initial pressure parameter. The initial pressure parameter comprises at least one of a fracture initiation pressure and a pump pressure peak value.

[0124] The engineering parameter determining unit is configured to obtain the initial engineering parameter based on the initial fracturing fluid parameter and the initial pressure parameter.

[0125] According to an embodiment of the present application, the engineering parameter prediction model is obtained by the following modules:

[0126] The obtaining module is configured to obtain sample geological parameters, sample crack parameters, and sample engineering parameters.

[0127] The first training module is configured to take the sample geological parameters as input data and the sample crack parameters as labels to train the initial first prediction module to obtain the trained first prediction module.

[0128] The second training module is configured to take the sample geological parameters and the sample crack parameters as input data and the sample engineering parameters as labels to train the initial second prediction module to obtain the trained second prediction module.

[0129] The model determining module is configured to obtain the engineering parameter prediction model based on the first prediction module and the second prediction module.

[0130] According to an embodiment of the present application, the simulation module can comprise:

[0131] a conversion submodule, configured to perform format conversion processing on the geological parameters and the initial engineering parameters to obtain geological parameters in a target format and initial engineering parameters in the target format, the target format matching the finite element numerical simulation model.

[0132] a filling submodule, configured to fill the geological parameters in the target format and the initial engineering parameters in the target format into a preset template to obtain a numerical simulation file.

[0133] a simulation submodule, configured to input the numerical simulation file into the finite element numerical simulation model to perform numerical simulation on the to-be-constructed stratum under the initial engineering parameters.

[0134] a collection submodule, configured to collect crack parameters in a preset time interval during the numerical simulation process to obtain crack parameters at different time points.

[0135] According to an embodiment of the present application, the adjustment module can comprise:

[0136] a volume calculation submodule, configured to perform integral calculation on a volume of a crack generated in the hydraulic fracturing simulation process based on the crack parameters to obtain a simulation volume of the crack.

[0137] an adjustment submodule, configured to, in a case where the simulation volume does not satisfy a target volume, adjust the initial engineering parameters based on variation trend information of the crack parameters in the numerical simulation process to obtain updated engineering parameters; the target volume is determined based on target crack parameters.

[0138] According to an embodiment of the present application, the adjustment submodule can comprise:

[0139] an adjustment unit, configured to, in a case where the variation trend information indicates that a crack size tends to be stable, adjust the initial engineering parameters.

[0140] an execution unit, configured to, in a case where the variation trend information indicates that the crack size tends to increase, not adjust the initial engineering parameters.

[0141] According to an embodiment of the present application, the crack parameters comprise a crack width and a crack length; and the variation trend information is determined by the following units:

[0142] a first determination unit, configured to determine a change rate of the crack based on the crack width and / or the crack length at adjacent time points.

[0143] a second determination unit, configured to determine the variation trend information of the crack based on the change rate of the crack.

[0144] According to an embodiment of the present application, the second determination module can comprise:

[0145] a fracture updating unit configured to perform hydraulic fracturing simulation on the formation to be treated under the updated engineering parameters to obtain updated fracture parameters.

[0146] a parameter determining unit configured to obtain target engineering parameters based on the initial engineering parameters and the at least one set of updated engineering parameters in the numerical simulation process, when the simulated volume of the fracture meets a target volume, the simulated volume being determined based on the updated fracture parameters.

[0147] Any one or more of the modules, sub-modules, units, sub-units according to the embodiments of the present application, or at least part of the functions of any one or more of the modules, sub-modules, units, sub-units according to the embodiments of the present application, can be implemented in one module. Any one or more of the modules, sub-modules, units, sub-units according to the embodiments of the present application can be split into multiple modules for implementation. Any one or more of the modules, sub-modules, units, sub-units according to the embodiments of the present application can be implemented at least in part as a hardware circuit, for example, a field programmable gate array (FPGA), a programmable logic array (PLA), a system on chip, a system on board, a system on package, an application specific integrated circuit (ASIC), or any other reasonable manner of hardware or firmware through integration or packaging of circuits, or in any one of software, hardware and firmware or in an appropriate combination of any of the above. Alternatively, one or more of the modules, sub-modules, units, sub-units according to the embodiments of the present application can be implemented at least in part as computer program modules, which can perform corresponding functions when the computer program modules are run.

[0148] For example, any multiple of the first determining module 410, the simulating module 420, the adjusting module 430 and the second determining module 440 can be combined in one module / unit / sub-unit for implementation, or any one of the modules / units / sub-units can be split into multiple modules / units / sub-units. Alternatively, at least part of the functions of one or more of the modules / units / sub-units can be combined with at least part of the functions of other modules / units / sub-units, and implemented in one module / unit / sub-unit. According to embodiments of the present application, at least one of the first determining module 410, the simulating module 420, the adjusting module 430 and the second determining module 440 can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on chip, a system on board, a system in package, an application specific integrated circuit (ASIC), or any other reasonable manner of integrating or packaging a circuit, etc. in hardware or firmware, or in any one of software, hardware and firmware or in a proper combination of any of them. Alternatively, at least one of the first determining module 410, the simulating module 420, the adjusting module 430 and the second determining module 440 can be at least partially implemented as a computer program module which, when executed, can perform the corresponding functions.

[0149] It should be noted that the device part for determining the hydraulic fracturing construction parameter in the embodiments of the present application corresponds to the method part for determining the hydraulic fracturing construction parameter in the embodiments of the present application, and the device part for determining the hydraulic fracturing construction parameter is described in the method part for determining the hydraulic fracturing construction parameter, which will not be described here.

[0150] The embodiments of the present application are described above. However, these embodiments are only for illustrative purposes, and are not intended to limit the scope of the present application. Although each of the embodiments is described above, this does not mean that the measures in each of the embodiments cannot be used advantageously in combination. The scope of the present application is defined by the appended claims and their equivalents. Without departing from the scope of the present application, those skilled in the art can make various substitutions and modifications, which should all fall within the scope of the present application.

Claims

1. A method for determining hydraulic fracturing operation parameters, comprising: inputting geological parameters of a formation to be fractured into an engineering parameter prediction model to obtain initial engineering parameters, the initial engineering parameters representing operation parameters for hydraulic fracturing of the formation to be fractured; performing numerical simulation of hydraulic fracturing of the formation to be fractured under the initial engineering parameters by using a finite element numerical simulation model to obtain simulated fracture parameters; based on the simulated fracture parameters, target fracture parameters, and the initial engineering parameters, obtaining updated engineering parameters, the target fracture parameters representing ideal parameters of fractures formed after hydraulic fracturing of the formation to be fractured; based on the initial engineering parameters and at least one set of updated engineering parameters in the numerical simulation process, obtaining target engineering parameters.

2. The method of claim 1, wherein, the engineering parameter prediction model comprises a first prediction module and a second prediction module; the inputting of the geological parameters of the formation to be fractured into the engineering parameter prediction model to obtain the initial engineering parameters comprises: inputting the geological parameters of the formation to be fractured into the first prediction module to obtain the target fracture parameters; inputting the geological parameters and the target fracture parameters into the second prediction module to obtain the initial engineering parameters.

3. The method of claim 2, wherein, the second prediction module comprises a first prediction unit and a second prediction unit, and the inputting of the geological parameters and the target fracture parameters into the second module to obtain the initial engineering parameters comprises: inputting the geological parameters and the target fracture parameters into the first prediction unit to obtain initial fracturing fluid parameters, the initial fracturing fluid parameters comprising at least one of fracturing fluid type, fracturing fluid concentration, fracturing fluid displacement, proppant concentration, and fracturing fluid injection duration; inputting the geological parameters, the target fracture parameters, and the initial fracturing fluid parameters into the second prediction unit to obtain initial pressure parameters, the initial pressure parameters comprising at least one of fracture initiation pressure and pump pressure peak value; based on the initial fracturing fluid parameters and the initial pressure parameters, obtaining the initial engineering parameters.

4. The method of claim 1, wherein, the adjusting of the initial engineering parameters based on the simulated fracture parameters and the target fracture parameters to obtain updated engineering parameters comprises: based on the simulated fracture parameters, performing integral calculation on a volume of fractures generated in the hydraulic fracturing simulation process to obtain a simulated volume of the fractures; in a case where the simulated volume does not satisfy a target volume, adjusting the initial engineering parameters based on change trend information of the simulated fracture parameters in the numerical simulation process to obtain updated engineering parameters, the target volume being determined based on the target fracture parameters.

5. The method of claim 4, wherein, the adjusting of the initial engineering parameters based on the change trend information of the simulated fracture parameters in the numerical simulation process comprises: in a case where the change trend information represents that the fracture size tends to be stable, adjusting the initial engineering parameters; in a case where the change trend information represents that the fracture size tends to increase, not adjusting the initial engineering parameters.

6. The method of claim 4 or 5, wherein, the simulated fracture parameters comprise fracture width and fracture length, and the change trend information is determined by: determine a change rate of the crack based on the crack width and / or crack length at adjacent time points; determine change trend information of the crack based on the change rate of the crack.

7. The method of claim 1, wherein, obtain a target engineering parameter based on the initial engineering parameter and at least one set of updated engineering parameters in a numerical simulation process, including: continue to perform hydraulic fracturing simulation on the formation to be constructed under the updated engineering parameter to obtain updated crack parameters; obtain the target engineering parameter based on the initial engineering parameter and at least one set of updated engineering parameters in a numerical simulation process when the simulation volume of the crack meets the target volume, and the simulation volume is determined based on the updated crack parameters.

8. The method of claim 1, wherein, the numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameter by using the finite element numerical simulation model, to obtain numerically simulated crack parameters, including: perform format conversion processing on the geological parameters and the initial engineering parameter to obtain geological parameters in a target format and initial engineering parameters in a target format, and the target format matches the finite element numerical simulation model; fill the geological parameters in the target format and the initial engineering parameters in the target format into a preset template to obtain a numerical simulation file; input the numerical simulation file into the finite element numerical simulation model to perform numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameter; collect crack parameters at a preset time interval in the numerical simulation process to obtain crack parameters at different time points.

9. The method of claim 1, wherein, The engineering parameter prediction model is obtained by the following method: obtain sample geological parameters, sample crack parameters and sample engineering parameters; train an initial first prediction module with the sample geological parameters as input data and the sample crack parameters as labels to obtain a trained first prediction module; train an initial second prediction module with the sample geological parameters and sample crack parameters as input data and the sample engineering parameters as labels to obtain a trained second prediction module; obtain the engineering parameter prediction model based on the first prediction module and the second prediction module.

10. A device for determining hydraulic fracturing construction parameters, comprising: a first determination module configured to input geological parameters of a formation to be constructed into an engineering parameter prediction model to obtain initial engineering parameters, the initial engineering parameters representing construction parameters for hydraulic fracturing of the formation to be constructed; a simulation module configured to perform numerical simulation of hydraulic fracturing of the formation to be constructed under the initial engineering parameters by using a finite element numerical simulation model to obtain numerically simulated crack parameters; an adjustment module configured to adjust the initial engineering parameters based on the crack parameters and target crack parameters to obtain updated engineering parameters, the target crack parameters representing ideal parameters of a crack formed after hydraulic fracturing of the formation to be constructed; a second determination module configured to obtain a target engineering parameter based on the initial engineering parameter and at least one set of updated engineering parameters in a numerical simulation process.

Images