Method and device for optimizing well spacing of oil well in edge and bottom water reservoir

Abstract

The application relates to an oil well well spacing optimization method and device for edge-bottom water reservoirs, and the method comprises the following steps: based on oil well well spacing and parameter data, the pressure distribution of the edge-bottom water reservoir under the condition that an arbitrary number of oil wells are simultaneously and stably produced is calculated by using a mirror image superposition principle; based on the pressure distribution of the edge-bottom water reservoir, the movement trajectory of fluid in the edge-bottom water reservoir is calculated and drawn by using a Pollock method, and the movement trajectory of the fluid is a streamline; the water saturation at an arbitrary time and an arbitrary position along the streamline is calculated by using a Buckley-Leverett method, so that the water saturation distribution in a two-dimensional simplified model is obtained, and the time for the water drive front saturation on each streamline to move from a supply boundary to the bottom of the oil well is calculated, so that the water drive front breakthrough time is determined; based on the water drive front breakthrough time, a relationship curve between the oil well well spacing and the cumulative oil production is drawn, and the optimal oil well well spacing of the edge-bottom water reservoir is determined.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field development technology, specifically to a method and apparatus for optimizing well spacing in edge-bottom water reservoirs. Background Technology

[0002] Well spacing is a crucial factor influencing key development indicators such as reservoir recovery rate, determining the effectiveness and economic benefits of reservoir development. Therefore, optimizing well spacing is an important research objective in the process of developing reservoir development plans.

[0003] Currently, the commonly used method for optimizing well spacing in oil wells is reservoir numerical simulation. This method is based on a three-dimensional geological model and simulates the dynamic changes in fluid distribution in the reservoir under certain well spacing and production regimes. It also assists reservoir researchers in optimizing well spacing by predicting development indicators such as water breakthrough time and cumulative oil production.

[0004] However, this method requires a high degree of accuracy in the three-dimensional geological model. But in the well location optimization stage, the understanding of the reservoir is not yet in-depth, making it difficult to establish an accurate three-dimensional geological model and accurately characterize the heterogeneity of the reservoir, which restricts the optimization of well spacing. Furthermore, when the viscosity difference between oil and water is small, the reservoir numerical simulation method cannot accurately characterize the conical advance of the oil-water interface, resulting in inaccurate simulation results of oil well development indicators, which also restricts the optimization of well spacing. At the same time, the reservoir numerical simulation method has high requirements for computer hardware and software and takes a long time to calculate, making it difficult to carry out rapid well spacing optimization work. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a method and apparatus for optimizing well spacing in edge-bottom water reservoirs. This method and apparatus can achieve efficient and accurate optimization of well spacing in edge-bottom water reservoirs based on the prediction and analysis of reservoir development effects under different well spacing conditions.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The well spacing optimization method for edge-bottom water reservoirs described in this invention includes the following steps:

[0008] Based on well spacing and parameter data, the pressure distribution of edge-bottom water reservoirs under stable production conditions of any number of oil wells is calculated using the principle of mirror superposition.

[0009] Based on the pressure distribution of edge-bottom water reservoirs, the Pollock method is used to calculate and plot the fluid motion trajectory in edge-bottom water reservoirs, and the fluid motion trajectory is the streamline.

[0010] Using the Buckley-Leverett method, the water saturation at any time and location along the streamline is calculated to obtain the water saturation distribution in the two-dimensional simplified model. The time it takes for the water drive front saturation to move from the supply boundary to the bottom of the well on each streamline is also calculated to determine the water drive front breakthrough time.

[0011] Based on the breakthrough time at the water drive front, a curve showing the relationship between well spacing and cumulative oil production was plotted, and the optimal well spacing for edge-bottom water reservoirs was determined.

[0012] The well spacing optimization method, preferably, involves calculating the pressure distribution of a bottom-water reservoir under stable production conditions using the mirror superposition principle, specifically including the following steps:

[0013] The edge-bottom water-oil reservoir is simplified into a two-dimensional rectangular model with three closed boundaries and one supply boundary.

[0014] Based on the two-dimensional rectangular model, using the principle of mirror superposition, we can obtain formula (1). Formula (1) is used to calculate the pressure drop distribution caused by the production of a single oil well in the edge-bottom water reservoir. If there are multiple oil wells producing, the pressure drop caused by the production of each oil well is accumulated to obtain the overall pressure drop distribution of the reservoir.

[0015] Based on the overall pressure drop distribution of the reservoir, the pressure distribution in the reservoir is calculated using formula (2);

[0016] Wherein, formula (1) and formula (2) are respectively:

[0017]

[0018] a=2ih±a;i=0,±1,±2,±3...±∞

[0019] P(x,y)=P e (x,y)+∑ΔP(x,y) (2)

[0020] In the formula: P is the reservoir pressure; ΔP is the pressure drop; P e q represents the original reservoir pressure; q represents the well production rate; μ o α is the viscosity of crude oil; K is the permeability; x is the X-axis coordinate; y is the Y-axis coordinate; α is the location of the oil well; a is the distance of the oil well from its left closed boundary; l is the distance of the oil well from the supply boundary; L is the height of the reservoir; h is the length of the reservoir.

[0021] The well spacing optimization method, preferably, involves using the Pollock method to calculate and plot the fluid movement trajectory in the edge-bottom water reservoir, where the fluid movement trajectory is the streamline, and specifically includes the following steps:

[0022] The basic assumption of the Pollock method is that within a grid, the velocity components of fluid particles along each coordinate axis change linearly;

[0023] Based on the pressure distribution in the reservoir, Darcy's formula is used to calculate the velocity distribution of fluid particles in the reservoir;

[0024] Based on the velocity distribution, calculate the (x, y) coordinates of the fluid particle when it enters and exits a grid, and connect the coordinates of the fluid particle through each grid to obtain its streamline.

[0025] For a two-dimensional rectangular model of a bottom-water reservoir, the Pollock method can be used to obtain several (x, y) coordinate points that a fluid particle passes through as it moves from any position on the supply boundary to the bottom of the well. Connecting these points will yield the streamlines in the two-dimensional rectangular model.

[0026] The well spacing optimization method, preferably, employs the Buckley-Leverett method to calculate the water saturation at any time and location along streamlines, thereby obtaining the water saturation distribution in a simplified two-dimensional model. It also calculates the time it takes for the water drive front saturation to move from the supply boundary to the bottom of the well on each streamline, thus determining the water drive front breakthrough time. Specifically, this method includes the following steps:

[0027] For the mainstream line between the oil well and the supply boundary, i.e. the vertical line from the oil well to the supply boundary, the water drive front breakthrough time is calculated using formula (3).

[0028] Based on the breakthrough time of the water drive front, calculate the position of arbitrary water saturation on each streamline;

[0029] Connecting the coordinates of the same water saturation on each streamline yields the water saturation contour lines, thus completing the calculation and drawing of the water saturation distribution in the reservoir;

[0030] Formula (3) is:

[0031]

[0032] In the formula, t is time; L is distance; φ is porosity; v is velocity; f' is the derivative of the flow rate equation; S w Water saturation;

[0033] Wherein, the parameter f′(S) in the formula w The result can be obtained by formulas (4)-(6):

[0034]

[0035]

[0036]

[0037] In the formula, λ o λ represents the fluidity of crude oil. w The fluidity of water; μ w The viscosity of water; K rw K represents the relative permeability of the aqueous phase. ro K represents the relative permeability of the oil phase. rw o K represents the endpoint value of the relative permeability of the aqueous phase. ro o The relative permeability of the oil phase is the endpoint value; Δρ is the density difference between water and oil; g is the gravitational acceleration; θ is the dip angle of the reservoir; S or S represents residual oil saturation. wi ρ is the bound water saturation; n is the aqueous phase index; m is the oil phase index; K is the permeability; μ o This refers to the viscosity of crude oil.

[0038] The method for optimizing well spacing, preferably, involves plotting the relationship curve between well spacing and cumulative oil production, and determining the optimal well spacing for edge-bottom water reservoirs, specifically including the following steps:

[0039] The cumulative oil production at the breakthrough moment of the water drive front is calculated based on the number of oil wells, daily oil production, and water drive front breakthrough time.

[0040] Determine the cumulative oil production under different well spacing conditions, and plot the relationship curve between well spacing and cumulative oil production;

[0041] Find the inflection point of the curve in the relationship curve diagram, which is the highest value of cumulative oil production, and determine the well spacing corresponding to this value. This well spacing is the optimal well spacing for the edge-bottom water reservoir.

[0042] The well spacing optimization device for edge-bottom water reservoirs of the present invention includes:

[0043] The first processing unit is used to calculate the pressure distribution of a bottom water reservoir under stable production conditions for any number of oil wells using the principle of mirror superposition.

[0044] The second processing unit is used to calculate and plot the fluid movement trajectory in the edge-bottom water reservoir based on the pressure distribution of the edge-bottom water reservoir using the Pollock method. The fluid movement trajectory is the streamline.

[0045] The third processing unit is used to calculate the water saturation at any time and any location along the streamline using the Buckley-Leverett method, thereby obtaining the water saturation distribution in the two-dimensional simplified model, and calculating the time it takes for the water drive front saturation on each streamline to move from the supply boundary to the bottom of the well, thereby determining the water drive front breakthrough time.

[0046] The fourth processing unit is used to plot the relationship curve between well spacing and cumulative oil production based on the breakthrough time of the water drive front, and to determine the optimal well spacing for edge-bottom water reservoirs.

[0047] The present invention also provides a computer storage medium storing a computer program thereon, wherein the computer program, when executed by a processor, implements the steps of the method for optimizing the well spacing of the edge-bottom water reservoir.

[0048] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the well spacing optimization method for the edge-bottom water reservoir.

[0049] The present invention has the following advantages due to the adoption of the above technical solutions:

[0050] (1) This invention uses the principle of mirror superposition to calculate the pressure distribution of the reservoir under stable production conditions of oil wells, and uses the Pollock streamline method to calculate the movement trajectory of oil and water in the reservoir. Based on this, the Buckley-Leverett method is applied to predict the distribution of oil and water in the reservoir, forming a semi-analytical oil well spacing optimization method, which can achieve efficient and accurate optimization of oil well spacing in edge and bottom water reservoirs.

[0051] (2) The semi-analytical well spacing optimization method established in this invention can predict reservoir development indicators under different well spacing conditions, including: water drive front breakthrough time, cumulative oil production at water drive front breakthrough, and water saturation distribution. Attached Figure Description

[0052] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0053] Figure 1 This is a schematic diagram of a simplified two-dimensional rectangular model of a water-oil reservoir at the edge and bottom;

[0054] Figure 2 This is a diagram showing the reservoir pressure distribution during production of an oil well in a bottom-water reservoir.

[0055] Figure 3 This is a streamline distribution diagram of an oil well in a bottom-water reservoir during production.

[0056] Figure 4 This is a schematic diagram of the main production line of an oil well in a bottom-water reservoir.

[0057] Figure 5 This is a map showing the water saturation distribution at the moment of breakthrough at the water drive front;

[0058] Figure 6 This is a map showing the water saturation distribution under different well spacing conditions;

[0059] Figure 7 It is a curve showing the relationship between well spacing and cumulative oil production. Detailed Implementation

[0060] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0061] This invention provides a method for optimizing well spacing in edge-bottom water reservoirs. It utilizes the principle of mirror superposition to calculate the reservoir pressure distribution under stable production conditions and employs the Pollock streamline method to calculate the movement trajectories of oil and water within the reservoir. Based on this, the Buckley-Leverett method is applied to predict the distribution of oil and water in the reservoir, establishing a semi-analytical well spacing optimization method. This invention enables efficient and accurate optimization of well spacing in edge-bottom water reservoirs based on the prediction and analysis of reservoir development effects under different well spacing conditions.

[0062] This invention provides a method for optimizing well spacing in edge-bottom water reservoirs, comprising the following steps:

[0063] (1) Based on the well spacing and parameter data, the pressure distribution of the edge-bottom water reservoir under the condition of simultaneous stable production of any number of oil wells is calculated by using the mirror superposition principle.

[0064] (2) Based on the pressure distribution of the edge-bottom water reservoir, the Pollock method is used to calculate and plot the fluid motion trajectory in the edge-bottom water reservoir. The fluid motion trajectory is the streamline.

[0065] (3) Using the Buckley-Leverett method, the water saturation at any time and any position along the streamline is calculated to obtain the water saturation distribution in the two-dimensional simplified model, and the time it takes for the water drive front saturation on each streamline to move from the supply boundary to the bottom of the well is calculated to determine the water drive front breakthrough time.

[0066] (4) Based on the breakthrough time of the water drive front, draw the curve of the relationship between the well spacing and the cumulative oil production, and determine the optimal well spacing for the edge-bottom water reservoir.

[0067] In the above embodiments, preferably, the step of calculating the pressure distribution of a bottom-water reservoir under stable production conditions of any number of oil wells using the mirror superposition principle specifically includes the following steps:

[0068] ①Simplify the edge-bottom water-oil reservoir into a two-dimensional rectangular model with three closed boundaries and one supply boundary, such as... Figure 1 As shown;

[0069] ②Based on the two-dimensional rectangular model, using the principle of mirror superposition, we can obtain formula (1). We can use formula (1) to calculate the pressure drop distribution caused by the production of a single oil well in the edge-bottom water reservoir. If there are multiple oil wells producing, we can sum up the pressure drop caused by the production of each oil well to obtain the overall pressure drop distribution of the reservoir.

[0070] ③ Based on the overall pressure drop distribution of the reservoir, the pressure distribution in the reservoir is calculated using formula (2);

[0071] Wherein, formula (1) and formula (2) are respectively:

[0072]

[0073] a=2ih±a;i=0,±1,±2,±3...±∞

[0074] P(x,y)=P e (x,y)+∑ΔP(x,y) (2)

[0075] In the formula: P is the reservoir pressure; ΔP is the pressure drop; P e q represents the original reservoir pressure; q represents the well production rate; μ o α is the viscosity of crude oil; K is the permeability; x is the X-axis coordinate; y is the Y-axis coordinate; α is the location of the oil well; a is the distance of the oil well from its left closed boundary; l is the distance of the oil well from the supply boundary; L is the height of the reservoir; h is the length of the reservoir.

[0076] In the above embodiments, preferably, the step of calculating and plotting the fluid movement trajectory in the edge-bottom water reservoir using the Pollock method, wherein the fluid movement trajectory is a streamline, specifically includes the following steps:

[0077] ①The basic assumption of the Pollock method is that within a grid, the velocity components of fluid particles along each coordinate axis change linearly;

[0078] ②Based on the pressure distribution in the reservoir, the Darcy formula is used to calculate the velocity distribution of fluid particles in the reservoir;

[0079] ③ Based on the velocity distribution, calculate the (x, y) coordinates of the fluid particle when it enters and exits a grid, and connect the coordinates of the fluid particle through each grid to obtain its streamline;

[0080] ④ For a two-dimensional rectangular model of a water reservoir, the Pollock method can be used to obtain several (x, y) coordinate points that a fluid particle passes through as it moves from any position on the supply boundary to the bottom of the well. Connecting these points will give the streamlines in the two-dimensional rectangular model.

[0081] In the above embodiments, preferably, the Buckley-Leverett method is used to calculate the water saturation at any time and location along the streamline, thereby obtaining the water saturation distribution in the two-dimensional simplified model, and the time it takes for the water drive front saturation to move from the supply boundary to the bottom of the well on each streamline is calculated, thereby determining the water drive front breakthrough time. Specifically, this includes the following steps:

[0082] ①The breakthrough time of the water drive front is calculated using formula (3) for the mainstream line between the oil well and the supply boundary, i.e. the vertical line from the oil well to the supply boundary.

[0083] ② Based on the breakthrough time of the water drive front, calculate the position of any water saturation on each streamline;

[0084] ③ By connecting the coordinates of the same water saturation on each streamline, we can obtain the water saturation contour lines, thus completing the calculation and drawing of the water saturation distribution in the reservoir;

[0085] Formula (3) is:

[0086]

[0087] In the formula, t is time; L is distance; φ is porosity; v is velocity; f' is the derivative of the flow rate equation; S w Water saturation;

[0088] Wherein, the parameter f′(S) in the formula w The result can be obtained by formulas (4)-(6):

[0089]

[0090]

[0091]

[0092] In the formula, λ o λ represents the fluidity of crude oil. w The fluidity of water; μ w The viscosity of water; K rw K represents the relative permeability of the aqueous phase. ro K represents the relative permeability of the oil phase. rw o K represents the endpoint value of the relative permeability of the aqueous phase. roo The relative permeability of the oil phase is the endpoint value; Δρ is the density difference between water and oil; g is the gravitational acceleration; θ is the dip angle of the reservoir; S or S represents residual oil saturation. wi ρ is the bound water saturation; n is the aqueous phase index; m is the oil phase index; K is the permeability; μ o This refers to the viscosity of crude oil.

[0093] In the above embodiments, preferably, the step of plotting the relationship curve between oil well spacing and cumulative oil production, and determining the optimal oil well spacing for edge-bottom water reservoirs, specifically includes the following steps:

[0094] ① Calculate the cumulative oil production at the breakthrough moment of the water drive front based on the number of oil wells, daily oil production, and water drive front breakthrough time;

[0095] ② Determine the cumulative oil production under different well spacing conditions, and plot the relationship curve between well spacing and cumulative oil production;

[0096] ③ Locate the inflection point of the curve in the relationship curve diagram, which is the highest value of cumulative oil production, and determine the well spacing corresponding to this value. This well spacing is the optimal well spacing for the bottom water reservoir.

[0097] Example 1:

[0098] (1) Basic data preparation

[0099] Taking the deployment of an oil well in a bottom-water reservoir as an example, the values ​​of the required parameters are shown in Table 1.

[0100] Table 1. Parameters required for calculation and their values.

[0101] parameter numerical values Reservoir length (m) 1000 Reservoir height (m) 120 Permeability (mD) 100 Porosity 0.3 Original reservoir pressure (MPa) 20 Bound water saturation 0.2 Residual oil saturation 0.3 Distance (m) of the oil well from its left closed boundary 500 Distance from the oil well to the supply boundary (m) 50 Crude oil viscosity (cP) 0.5 Viscosity of water (cP) 0.4 <![CDATA[Water-oil density difference (kg / m 3 )]]> 250 <![CDATA[Acceleration due to gravity (m / s 2 )]]> 9.8 Reservoir dip angle (°) 90 <![CDATA[Oil well production (m 3 / d)]]> 100 Water phase relative permeability endpoint value 0.6 oil phase relative permeability endpoint value 1 Aqueous phase index 1.4 Oil phase index 2.5

[0102] (2) Calculate the pressure distribution in the reservoir

[0103] Based on the parameter values ​​in Table 1, formula (1) is used to calculate the pressure drop caused by the oil well in the reservoir, and formula (2) is used to calculate the pressure distribution in the reservoir. The calculated pressure distribution diagram is shown below. Figure 2 As shown.

[0104] (3) Calculate streamline distribution in reservoir

[0105] Based on the pressure distribution of the reservoir, the Pollock streamline method was used to calculate and plot the fluid flow trajectory from the supply boundary to the bottom of the well. The streamline distribution during production in a well within a side-bottom water reservoir is shown in the diagram. Figure 3 As shown.

[0106] (4) Calculate the breakthrough time of the water drive front

[0107] The main trendline between the oil well and the supply boundary, i.e. Figure 4 The blue streamline shown is used to calculate the water-drive leading edge breakthrough time using formula (3), and the result is 104d.

[0108] Based on the breakthrough moment of the water-drive front, the water saturation at different locations on each streamline is further calculated. Connecting the coordinates of the same water saturation on each streamline yields water saturation contour lines, thus completing the calculation and plotting of the water saturation distribution. The water saturation distribution at the breakthrough moment of the water-drive front is shown in the figure below. Figure 5 As shown.

[0109] (5) Plot the curve showing the relationship between well spacing and cumulative oil production.

[0110] Under the data conditions of this embodiment, based on the water drive front breakthrough time calculated in step (4), the cumulative oil production of a well deployed in the edge-bottom water reservoir at the water drive front breakthrough time can be calculated to be 10400 m³. 3 .

[0111] By changing the well spacing, steps (1)-(4) were repeated to calculate the water drive front breakthrough time, cumulative oil production, and water saturation distribution under different well spacing conditions. Table 2 shows the water drive front breakthrough time and cumulative oil production under different well spacing conditions, and Table 2 shows the water saturation distribution. Figure 6 As shown.

[0112] Table 2. Water drive front breakthrough time and cumulative oil production under different well spacing conditions.

[0113] Well spacing / m Water drive leading edge breakthrough time / d <![CDATA[Cumulative oil production / m 3 > 500 104 10400 300 102 20400 250 99 29700 200 98 39200 150 84 42000 100 68 40800

[0114] Based on the results in Table 2, a curve showing the relationship between well spacing and cumulative oil production was plotted, as follows: Figure 7 As shown. Search Figure 7 The inflection point of the curve, i.e., the highest cumulative oil production, is 42,000 m³. 3 The well spacing corresponding to this cumulative oil production is 150m, which is the optimal well spacing for the edge-bottom water reservoir in this case.

[0115] Example 2:

[0116] This invention also provides a well spacing optimization device for edge-bottom water reservoirs, comprising:

[0117] The first processing unit is used to calculate the pressure distribution of a bottom water reservoir under stable production conditions for any number of oil wells using the principle of mirror superposition.

[0118] The second processing unit is used to calculate and plot the fluid movement trajectory in the edge-bottom water reservoir based on the pressure distribution of the edge-bottom water reservoir using the Pollock method. The fluid movement trajectory is the streamline.

[0119] The third processing unit is used to calculate the water saturation at any time and any location along the streamline using the Buckley-Leverett method, thereby obtaining the water saturation distribution in the two-dimensional simplified model, and calculating the time it takes for the water drive front saturation on each streamline to move from the supply boundary to the bottom of the well, thereby determining the water drive front breakthrough time.

[0120] The fourth processing unit is used to plot the relationship curve between well spacing and cumulative oil production based on the breakthrough time of the water drive front, and to determine the optimal well spacing for edge-bottom water reservoirs.

[0121] Example 3:

[0122] The present invention also provides a computer storage medium storing a computer program thereon, wherein the computer program, when executed by a processor, implements the steps of the method for optimizing the well spacing of the edge-bottom water reservoir.

[0123] Example 4:

[0124] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the well spacing optimization method for the edge-bottom water reservoir.

[0125] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for optimizing well spacing in edge-bottom water reservoirs, characterized in that, Includes the following steps: Based on well spacing and parameter data, the pressure distribution of edge-bottom water reservoirs under stable production conditions of any number of oil wells is calculated using the principle of mirror superposition. Based on the pressure distribution of edge-bottom water reservoirs, the Pollock method is used to calculate and plot the fluid motion trajectory in edge-bottom water reservoirs, and the fluid motion trajectory is the streamline. Using the Buckley-Leverett method, the water saturation at any time and location along the streamline is calculated to obtain the water saturation distribution in the two-dimensional simplified model. The time it takes for the water drive front saturation to move from the supply boundary to the bottom of the well on each streamline is also calculated to determine the water drive front breakthrough time. Based on the breakthrough time at the water drive front, a curve showing the relationship between well spacing and cumulative oil production was plotted, and the optimal well spacing for edge-bottom water reservoirs was determined.

2. The method for optimizing oil well spacing according to claim 1, characterized in that, The method of calculating the pressure distribution of a bottom-water reservoir under stable production conditions using the principle of mirror superposition specifically includes the following steps: The edge-bottom water-oil reservoir is simplified into a two-dimensional rectangular model with three closed boundaries and one supply boundary. Based on the two-dimensional rectangular model, using the principle of mirror superposition, we can obtain formula (1). Formula (1) is used to calculate the pressure drop distribution caused by the production of a single oil well in the edge-bottom water reservoir. If there are multiple oil wells producing, the pressure drop caused by the production of each oil well is accumulated to obtain the overall pressure drop distribution of the reservoir. Based on the overall pressure drop distribution of the reservoir, the pressure distribution in the reservoir is calculated using formula (2); Wherein, formula (1) and formula (2) are respectively: a=2ih±a;i=0,±1,±2,±3...±∞ P(x,y)=P e (x,y)+∑ΔP(x,y) (2) In the formula: P is the reservoir pressure; ΔP is the pressure drop; P e q represents the original reservoir pressure; q represents the well production rate; μ o α is the viscosity of crude oil; K is the permeability; x is the X-axis coordinate; y is the Y-axis coordinate; α is the location of the oil well; a is the distance of the oil well from its left closed boundary; l is the distance of the oil well from the supply boundary; L is the height of the reservoir; h is the length of the reservoir.

3. The method for optimizing oil well spacing according to claim 2, characterized in that, The method of using Pollock to calculate and plot the fluid movement trajectory in the edge-bottom water reservoir, where the fluid movement trajectory is the streamline, specifically includes the following steps: The basic assumption of the Pollock method is that within a grid, the velocity components of fluid particles along each coordinate axis change linearly; Based on the pressure distribution in the reservoir, Darcy's formula is used to calculate the velocity distribution of fluid particles in the reservoir; Based on the velocity distribution, calculate the (x, y) coordinates of the fluid particle when it enters and exits a grid, and connect the coordinates of the fluid particle through each grid to obtain its streamline. For a two-dimensional rectangular model of a bottom-water reservoir, the Pollock method can be used to obtain several (x, y) coordinate points that a fluid particle passes through as it moves from any position on the supply boundary to the bottom of the well. Connecting these points will yield the streamlines in the two-dimensional rectangular model.

4. The method for optimizing oil well spacing according to claim 1, characterized in that, The Buckley-Leverett method is used to calculate the water saturation at any time and location along streamlines, thereby obtaining the water saturation distribution in the two-dimensional simplified model. The time it takes for the water drive front saturation to move from the supply boundary to the bottom of the well on each streamline is also calculated to determine the water drive front breakthrough time. Specifically, the steps include the following: For the mainstream line between the oil well and the supply boundary, i.e. the vertical line from the oil well to the supply boundary, the water drive front breakthrough time is calculated using formula (3). Based on the breakthrough time of the water drive front, calculate the position of arbitrary water saturation on each streamline; Connecting the coordinates of the same water saturation on each streamline yields the water saturation contour lines, thus completing the calculation and drawing of the water saturation distribution in the reservoir; Formula (3) is: In the formula, t is time; L is distance; φ is porosity; v is velocity; f' is the derivative of the flow rate equation; S w Water saturation; Wherein, the parameter f′(S) in the formula w The result can be obtained by formulas (4)-(6): In the formula, λ o λ represents the fluidity of crude oil. w The fluidity of water; μ w The viscosity of water; K rw K represents the relative permeability of the aqueous phase. ro K represents the relative permeability of the oil phase. rw o K represents the endpoint value of the relative permeability of the aqueous phase. ro o The relative permeability of the oil phase is the endpoint value; Δρ is the density difference between water and oil; g is the gravitational acceleration; θ is the dip angle of the reservoir; S or S represents residual oil saturation. wi ρ is the bound water saturation; n is the aqueous phase index; m is the oil phase index; K is the permeability; μ o This refers to the viscosity of crude oil.

5. The method for optimizing oil well spacing according to claim 1, characterized in that, The process of plotting the curve relating well spacing to cumulative oil production and determining the optimal well spacing for edge-bottom water reservoirs includes the following steps: The cumulative oil production at the breakthrough moment of the water drive front is calculated based on the number of oil wells, daily oil production, and water drive front breakthrough time. Determine the cumulative oil production under different well spacing conditions, and plot the relationship curve between well spacing and cumulative oil production; Find the inflection point of the curve in the relationship curve diagram, which is the highest value of cumulative oil production, and determine the well spacing corresponding to this value. This well spacing is the optimal well spacing for the edge-bottom water reservoir.

6. A well spacing optimization device for edge-bottom water reservoirs, characterized in that, include: The first processing unit is used to calculate the pressure distribution of a bottom water reservoir under stable production conditions for any number of oil wells using the principle of mirror superposition. The second processing unit is used to calculate and plot the fluid movement trajectory in the edge-bottom water reservoir based on the pressure distribution of the edge-bottom water reservoir using the Pollock method. The fluid movement trajectory is the streamline. The third processing unit is used to calculate the water saturation at any time and any location along the streamline using the Buckley-Leverett method, thereby obtaining the water saturation distribution in the two-dimensional simplified model, and calculating the time it takes for the water drive front saturation on each streamline to move from the supply boundary to the bottom of the well, thereby determining the water drive front breakthrough time. The fourth processing unit is used to plot the relationship curve between well spacing and cumulative oil production based on the breakthrough time of the water drive front, and to determine the optimal well spacing for edge-bottom water reservoirs.

7. A computer storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the well spacing optimization method for oil well reservoirs with edge-bottom water as described in any one of claims 1-5.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the well spacing optimization method for edge-bottom water reservoirs as described in any one of claims 1-5.

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