Method and system for improving fan body deposition numerical simulation efficiency

Abstract

The invention relates to the technical field of oil exploration and development, in particular to a method and system for improving fan body deposition numerical simulation efficiency. Comprising the following steps: S1, obtaining related data of a to-be-simulated fan body; s2, dividing the sediment required by the fan body to be simulated into a plurality of micelles; s3, establishing grid coordinates, and setting initial coordinates of a plurality of micelles; s4, starting from the initial coordinate position, putting a plurality of micelles one by one; s5, calculating the deposition position of each micellar and the landform elevation after deposition based on a fast gradient descent algorithm; s6, through the step S5, the deposition positions of all the micelles and the landform elevation after deposition are obtained, and then the final model landform after deposition and the final deposition thickness are formed; the numerical simulation of the fan body deposition process is realized, the calculation efficiency can be remarkably improved, and the method is more suitable for long-period and large-scale geological process simulation with low precision requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of oil exploration and development, and particularly relates to a method and system for improving the numerical simulation efficiency of fan body deposition. Background Art

[0002] Sedimentation simulation experiments are of great significance in oil exploration and development practice as well as geological research. By restoring paleogeomorphic and paleocurrent information from known subsurface data and setting corresponding sedimentation simulation experiments based on this to simulate the sedimentation process of sand bodies, it can greatly help researchers understand and predict the changes of sand bodies. For example, by simulating different water flow velocities, sediment grain sizes and densities, researchers can observe and analyze the movement and distribution laws of sediments. Thus, revealing the causes of geological phenomena and predicting the spatio-temporal distribution of favorable sand bodies. As a new type of sedimentation simulation method, numerical sedimentation simulation has the advantages of low cost, short cycle, low degree of human intervention, and good reproducibility of experimental results compared with traditional physical experiments.

[0003] Currently, in numerical sedimentation simulation, the transportation and sedimentation process of sediments in water flow is mainly simulated by solving the state of each physical quantity in the Newtonian dynamics equation. This method has high accuracy, but the model is complex, the solution is difficult, and the calculation efficiency is low. It is mainly used for short-term computational fluid dynamics and water conservancy fields, and is not suitable for research in the geological field.

[0004] Therefore, there is an urgent need to provide a method and system for improving the numerical simulation efficiency of fan body deposition. Compared with the existing technology, it is applicable to long-term and large-scale calculations in geology to improve the calculation efficiency. Summary of the Invention

[0005] The present invention solves the technical problems existing in the prior art, and provides a method and system for improving the numerical simulation efficiency of fan body deposition.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for improving the numerical simulation efficiency of fan body deposition, comprising the following steps:

[0008] S1. Obtain data related to the fan body to be simulated;

[0009] S2. Divide the sediments required for the fan body to be simulated into several micro-masses;

[0010] S3. Establish a grid coordinate and set the initial coordinates of several micro-masses;

[0011] S4. Starting from the initial coordinate position, put several micro-masses one by one;

[0012] S5. Calculate the deposition position of each micro - mass and the geomorphic elevation after deposition based on the fast gradient descent algorithm;

[0013] S6. Through step S5, obtain the deposition positions of all micro - masses and the geomorphic elevations after deposition, and then form the final modeled geomorphology after deposition and the final deposition thickness.

[0014] Further, S5 specifically includes the following steps:

[0015] S501. Calculate the deposition position of the micro - mass through the fast gradient descent algorithm, where the deposition position is the position where the micro - mass naturally rolls down under the action of gravity and finally stops;

[0016] S502. Calculate the geomorphic elevation after deposition of the micro - mass.

[0017] Even further, step S502 specifically calculates the geomorphic elevation after deposition through the following formula:

[0018] H = H 0 +h

[0019] In the above formula, H represents the geomorphic elevation after deposition of a single micro - mass, H 0 is the initial geomorphic elevation of a single micro - mass, and h is the deposition thickness of the current grid of a single micro - mass.

[0020] Even further, the data related to the fan body to be simulated obtained in step S1 includes at least the mass of the sediment of the fan body to be simulated, the central position of the deposition of the fan body to be simulated, and the initial geomorphic information of the fan body to be simulated.

[0021] Even further, the deposition thickness of the current grid of a single micro - mass in step S502 is calculated through the following formula:

[0022]

[0023] In the above formula, h represents the deposition thickness of the current grid of a single micro - mass, m represents the mass of a single micro - mass, dx represents the grid size unit, and ρ represents the sediment density.

[0024] Even further, the mass of the micro - mass is calculated through the following formula:

[0025]

[0026] In the above formula, m represents the mass of each micro - mass, n represents the number of micro - masses, and M represents the mass of the sediment.

[0027] Even further, the initial positions of several micro - masses set in step S3 are the central position of the deposition of the fan body to be simulated.

[0028] Even further, S501 specifically includes the following steps:

[0029] (1) Calculate the gradient of the geomorphic function with respect to elevation;

[0030] (2) Update the position coordinates of the micro - clusters based on the gradient calculated in step (1):

[0031] (3) Repeat steps (1) - (2) until the stop condition is met.

[0032] Furthermore, in step (1) of S501, the gradient of the geomorphic function with respect to elevation is specifically calculated using the Library function in Mathematical or MATLAB or python.

[0033] Furthermore, in step (2) of S501, when the calculated gradient is the i - th when the stop condition is met, the position coordinates of the finally updated micro - cluster are expressed by the following formula:

[0034]

[0035]

[0036] In the above formula, represents the abscissa of the t - th micro - cluster after being regulated by the i - th gradient, represents the ordinate of the t - th micro - cluster after being regulated by the i - th gradient, represents the constant for regulating the abscissa of the micro - cluster in the gradient after the i - th calculation, represents the constant for regulating the ordinate of the micro - cluster in the gradient after the i - th calculation, represents the constant for regulating the abscissa of the micro - cluster in the gradient after the first calculation, represents the constant for regulating the ordinate of the micro - cluster in the gradient after the first calculation, x 0 represents the abscissa in the initial coordinates of the micro - cluster, y 0 represents the ordinate in the initial coordinates of the micro - cluster.

[0037] Furthermore, the stop condition described in step (3) of S501 is: reaching the set maximum number of iterations.

[0038] Furthermore, the stop condition described in step (3) of S501 is: the magnitude of the calculated gradient is less than the set threshold.

[0039] Furthermore, S6 specifically includes the following steps:

[0040] S601. Set the deposition position of each micro - cluster as a grid, and the elevation of the geomorphology after deposition of each micro - cluster is the elevation after deposition of this grid. The deposition positions and the elevations of the geomorphology after deposition of all micro - clusters constitute the final model geomorphology after deposition;

[0041] S602. Obtain the final deposition thickness based on the final deposited model geomorphology.

[0042] Furthermore, the specific method for obtaining the deposition thickness in S602 is as follows: Obtain the difference between the final deposited model geomorphology obtained in step S601 and the initial geomorphology to get the final deposition thickness.

[0043] A system for improving the numerical simulation efficiency of fan body deposition, including a first module, a second module, a third module, a fourth module, a fifth module, and a sixth module connected in sequence. The first module is used to execute the content in step S1, the second module is used to execute the content in step S2, the third module is used to execute the content in step S3, the fourth module is used to execute the content in step S4, the fifth module is used to execute the content in step S5, and the sixth module is used to execute the content in step S6.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0045] (1) The present invention realizes the numerical simulation of the fan body deposition process. Different from simulating the transportation and deposition process of sediments in water flow by solving the states of various physical quantities in Newton's dynamics equations, the method provided by the present invention can significantly improve the calculation efficiency and is more suitable for simulating geological processes with low precision requirements, long periods, and large scales. Description of the Drawings

[0046] Figure 1 is a flowchart of the method of the present invention.

[0047] Figure 2 is a three-dimensional schematic diagram of the fast gradient descent algorithm of the present invention.

[0048] Figure 3 is a planar schematic diagram of the fast gradient descent algorithm of the present invention.

[0049] Figure 4 is a schematic diagram of the final deposited model geomorphology of the present invention.

[0050] Figure 5 is a schematic diagram of the system of the present invention. Detailed Embodiments

[0051] The technical solutions of the present invention will be clearly described below in conjunction with the description of the drawings. Obviously, the described embodiments are not all the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0052] As Figure 1 shown, the present invention provides a method for improving the numerical simulation efficiency of fan body deposition, including the following steps:

[0053] S1. Obtain data related to the fan body to be simulated. The related data specifically includes the mass M of the sediment of the fan body to be simulated, the central position of the deposition of the fan body to be simulated, and the initial geomorphic information of the fan body to be simulated.

[0054] Furthermore, the related data of the fan body to be simulated are data defined by the user himself / herself and come from files stored by the user, such as files stored in json format or txt text format, and are obtained by using functions such as read and json.load in programming languages C or Python for reading.

[0055] Even further, the obtained initial geomorphic information of the fan body to be simulated includes at least the initial geomorphic elevation and the initial geomorphic function.

[0056] S2. Subdivide the sediment into several micro - masses, requiring that the sediment micro - mass is macroscopically small enough and microscopically large enough.

[0057] Furthermore, the mass of each micro - mass is specifically:

[0058]

[0059] In the above formula, m represents the mass of each micro - mass, n represents the number of micro - masses, and M represents the mass of the sediment.

[0060] S3. Set the grid coordinates, and set the coordinates of the central position of the deposition of the fan body obtained in step S1 as the initial coordinates of all micro - masses, denoted as (x 0 , y 0 ).

[0061] S4. Starting from the central position of the deposition of the fan body to be simulated, place the micro - masses one by one.

[0062] S5. Based on the fast gradient descent algorithm, calculate the deposition position, deposition thickness, and post - deposition geomorphic elevation of each micro - mass, specifically including the following steps:

[0063] S501. Calculate the deposition position of each micro - mass: For each micro - mass, calculate the position where the micro - mass naturally rolls down under the action of gravity and finally stops through the fast gradient descent algorithm. The position where the micro - mass finally stops is the deposition position of the micro - mass.

[0064] The specific steps of the fast gradient descent algorithm include:

[0065] (1) Through the functions and solvers dedicated to calculating gradients in existing computer software, calculate the gradient of the geomorphic function with respect to elevation. It should be noted that the gradient is a vector, whose direction points to the maximum growth direction of the function at the current geomorphic elevation position, and its magnitude represents the growth rate of the function in this direction;

[0066] Furthermore, the Library functions in Mathematical, MATLAB, or Python can be selected to calculate the gradient of the geomorphic function with respect to elevation.

[0067] Furthermore, the calculated gradient is expressed as:

[0068]

[0069] In the above formula, represents the gradient after the first calculation, represents the constant for regulating the abscissa of the microcluster in the gradient after the first calculation, represents the constant for regulating the ordinate of the microcluster in the gradient after the first calculation.

[0070] (2) Update the position information of the sediment microclusters, which is specifically expressed by the following formula:

[0071]

[0072]

[0073] In the above formula, is the abscissa of the t-th microcluster after the first regulation by the gradient, represents the ordinate of the t-th microcluster after the first regulation by the gradient, where t takes 1, 2, 3, …, n.

[0074] (3) Repeat steps (1)-(2) until the stop condition is met. The stop condition is reaching the set maximum number of iterations or the magnitude of the gradient being less than the set threshold (indicating that the minimum elevation has been approached).

[0075] Furthermore, when the gradient calculated when the stop condition is met is the position information of the finally updated microclusters is:

[0076]

[0077]

[0078] In the above formula, is the abscissa of the t-th microcluster after the i-th gradient regulation, is the ordinate of the t-th microcluster after the i-th gradient regulation, represents the constant for regulating the abscissa of the microcluster in the gradient after the i-th calculation, represents the constant for regulating the ordinate of the microcluster in the gradient after the i-th calculation.

[0079] S502. Calculate the sediment thickness at the deposition position of the microclusters, which is specifically expressed as:

[0080]

[0081] In the above formula, h represents the deposition thickness of a single micro - mass in the current grid, m represents the mass of a single micro - mass, dx represents the grid - size unit, and ρ represents the sediment density.

[0082] S503. Calculate the post - deposition geomorphic elevation of the micro - mass according to the deposition thickness of the micro - mass, which is expressed by the following formula:

[0083] H = H 0 + h

[0084] In the above formula, H represents the post - deposition geomorphic elevation of a single micro - mass, H 0 is the initial geomorphic elevation of a single micro - mass, H 0 is the input data from the user, and h is the deposition thickness of a single micro - mass in the current grid.

[0085] Furthermore, Figure 2 、 Figure 3 are the three - dimensional schematic diagram and the planar schematic diagram of the fast gradient descent algorithm.

[0086] S6. Obtain the deposition positions, deposition thicknesses, and post - deposition geomorphic elevations of n micro - masses through step S5 to form the final post - deposition model geomorphology and the final deposition thickness. Specifically, it includes the following steps:

[0087] S601. The deposition position of each micro - mass is represented as a grid, and the post - deposition geomorphic elevation of each micro - mass is the elevation after deposition of this grid. The deposition positions and post - deposition elevation geomorphologies of all micro - masses constitute the final post - deposition model geomorphology.

[0088] S602. Obtain the final deposition thickness according to the final post - deposition model geomorphology. Specifically: Subtract the initial geomorphology from the final post - deposition model geomorphology, and the difference is the final deposition thickness.

[0089] Furthermore, Figure 4 is the schematic diagram of the final post - deposition model geomorphology formed in step S6.

[0090] The present invention realizes the numerical simulation of the fan - body deposition process. Different from simulating the transportation and deposition process of sediments in water flow by solving the states of various physical quantities in the Newtonian dynamics equation, the method provided by the present invention can significantly improve the calculation efficiency and is more suitable for simulating geological processes with low precision requirements, long - term, and large - scale.

[0091] Such as Figure 5As shown in the figure, the present invention also provides a system for improving the numerical simulation efficiency of fan deposition, including a first module, a second module, a third module, a fourth module, a fifth module and a sixth module. The output end of the first module is connected to the input end of the second module, the output end of the second module is connected to the input end of the third module, the output end of the third module is connected to the input end of the fourth module, the output end of the fourth module is connected to the input end of the fifth module, and the output end of the fifth module is connected to the input end of the sixth module. The first module is used to execute the operation content in step S1, the second module is used to execute the operation content in step S2, the third module is used to execute the operation content in step S3, the fourth module is used to execute the operation content in step S4, the fifth module is used to execute the operation content in step S5, and the sixth module is used to execute the operation content in step S6. The data related to the fan to be simulated is used as the input of the first module, and the sixth module outputs the final deposited model landform and the final deposition thickness.

[0092] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than a limitation on the protection scope of the present invention. Any simple modification or equivalent replacement of the technical solution of the present invention by those of ordinary skill in the art does not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for improving the numerical simulation efficiency of fan deposition, characterized in that, it includes the following steps: S1. Obtain relevant data of the fan to be simulated; S2. Divide the sediment required for the fan to be simulated into several micro - masses; S3. Establish a grid coordinate and set the initial coordinates of several micro - masses; S4. Starting from the initial coordinate position, place several micro - masses one by one; S5. Calculate the deposition position of each micro - mass and the geomorphic elevation after deposition based on the fast gradient descent algorithm; S6. Through step S5, obtain the deposition positions of all micro - masses and the geomorphic elevation after deposition, and then form the final model geomorphology after deposition and the final deposition thickness.

2. A method for improving the numerical simulation efficiency of fan deposition according to claim 1, characterized in that, S5 specifically includes the following steps: S501. Calculate the deposition position of the micro - mass through the fast gradient descent algorithm, and the deposition position is the position where the micro - mass naturally rolls down under the action of gravity and finally stops; S502. Calculate the geomorphic elevation after deposition of the micro - mass.

3. A method for improving the numerical simulation efficiency of fan deposition according to claim 2, characterized in that, Step S502 specifically calculates the geomorphic elevation after deposition through the following formula: H = H 0 + h In the above formula, H represents the topographic elevation after the deposition of a single micro-mass, and H 0 is the initial topographic elevation of a single micro-mass, and h is the deposition thickness of a single micro-mass in the current grid.

4. A method for improving the numerical simulation efficiency of fan deposition according to claim 3, characterized in that, The relevant data of the fan to be simulated obtained in step S1 at least includes the mass of the sediment of the fan to be simulated, the central position of the fan deposition, and the initial geomorphic information of the fan to be simulated.

5. A method for improving the numerical simulation efficiency of fan deposition according to claim 4, characterized in that, The deposition thickness of a single micro - mass in the current grid in step S502 is calculated through the following formula: In the above formula, h represents the deposition thickness of a single micro - mass in the current grid, m represents the mass of a single micro - mass, dx represents the grid size unit, and ρ represents the sediment density.

6. A method for improving the numerical simulation efficiency of fan deposition according to claim 4, characterized in that, The mass of the micro - mass is calculated through the following formula: In the above formula, m represents the mass of each micro - mass, n represents the number of micro - masses, and M represents the mass of the sediment.

7. A method for improving the numerical simulation efficiency of fan deposition according to claim 4, characterized in that, The initial positions of several micro - masses set in step S3 are the central position of the fan deposition to be simulated.

8. A method for improving the numerical simulation efficiency of fan deposition according to claim 2, characterized in that, S501 specifically includes the following steps: (1) Calculate the gradient of the geomorphic function with respect to elevation; (2) Update the position coordinates of the micro - mass based on the gradient calculated in step (1): (3) Repeat steps (1) - (2) until the stop condition is met.

9. A method for improving the numerical simulation efficiency of fan deposition according to claim 8, characterized in that, Step (1) in S501 specifically uses the Library function in Mathematical or MATLAB or python to calculate the gradient of the geomorphic function with respect to elevation.

10. A method for improving the numerical simulation efficiency of fan body deposition according to claim 8, characterized in that, in step (2) of S501, when the calculated gradient is the i-th when the stop condition is met, the position coordinates of the finally updated microcluster are represented by the following formula: In the above formula, represents the abscissa of the t-th microcluster after the i-th gradient regulation, represents the ordinate of the t-th microcluster after the i-th gradient regulation, represents the constant for regulating the abscissa of the microcluster in the gradient after the i-th calculation, represents the constant for regulating the ordinate of the microcluster in the gradient after the i-th calculation, represents the constant for regulating the abscissa of the microcluster in the gradient after the first calculation, represents the constant for regulating the ordinate of the microcluster in the gradient after the first calculation, x 0 represents the abscissa in the initial coordinates of the microcluster, y 0 represents the ordinate in the initial coordinates of the microcluster.

11. A method for improving the numerical simulation efficiency of fan body deposition according to claim 8, characterized in that, the stop condition described in step (3) of S501 is: reaching the set maximum number of iterations.

12. A method for improving the numerical simulation efficiency of fan body deposition according to claim 8, characterized in that, the stop condition described in step (3) of S501 is: the magnitude of the calculated gradient is less than the set threshold.

13. A method for improving the numerical simulation efficiency of fan body deposition according to claim 2, characterized in that, S6 specifically includes the following steps: S601: Set the deposition position of each microcluster as a grid, and the geomorphic elevation after deposition of each microcluster is the elevation after deposition of the grid. The deposition positions and the geomorphic elevations after deposition of all microclusters constitute the final model geomorphology after deposition; S602: Obtain the final deposition thickness according to the final model geomorphology after deposition.

14. A method for improving the numerical simulation efficiency of fan body deposition according to claim 13, characterized in that, the specific method for obtaining the deposition thickness in S602 is: subtracting the difference between the initial geomorphology from the final model geomorphology after deposition obtained in step S601 to obtain the final deposition thickness.

15. A system using the method for improving the numerical simulation efficiency of fan body deposition according to any one of claims 1-14, characterized in that, it includes a first module, a second module, a third module, a fourth module, a fifth module and a sixth module connected in sequence. The first module is used to execute the content in step S1, the second module is used to execute the content in step S2, the third module is used to execute the content in step S3, the fourth module is used to execute the content in step S4, the fifth module is used to execute the content in step S5, and the sixth module is used to execute the content in step S6.

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