A method for splitting steam injection volume of different layers of a multi-layer commingled heavy oil reservoir steam stimulation well

Abstract

The application discloses a kind of different layer section steam injection amount splitting methods of multilayer commingling heavy oil reservoir steam huff and puff well, comprising: S1, obtains target oilfield well group steam injection parameter;S2, obtains the geologic reservoir parameter of each layer of target oil reservoir;S3, calculates target oil reservoir interlayer steam splitting coefficient and steam intake;S4, obtains the basic parameters of each small layer in target oil layer interwell geologic reservoir;S5, calculates the average formation coefficient between target oil reservoir steam injection well and steam channeling well;S6, calculates the splitting angle between target oil reservoir steam injection well and each steam channeling well;S7, calculates the splitting coefficient and steam intake between target oil reservoir steam injection well and each steam channeling well and the like steps.The application can determine steam injection amount and steam intake between layers and interwell in steam huff and puff process, solve the problem of lacking different layer section steam injection amount splitting method of multilayer commingling heavy oil reservoir steam huff and puff well, provide basis for determining reasonable steam injection amount in heavy oil thermal recovery oilfield steam huff and puff process.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field development, and particularly relates to a method for splitting the steam injection rate of different layers in a steam huff-and-puff well of a multi-layer commingled production heavy oil reservoir. Background Art

[0002] During multi-layer, multi-well steam stimulation, the reservoir is composed of multiple thin layers separated by interlayers. Due to differences in reservoir physical properties between the layers, the amount of injected steam absorbed varies between layers, resulting in interlayer differences in steam injection rates. Furthermore, during multi-well steam stimulation, differences in production pressure differentials between wells and differences in stimulation cycles inevitably lead to a certain pressure differential between the two wells. Furthermore, the presence of high-permeability pathways can lead to differences in steam absorption between a single well and surrounding wells, resulting in differences in steam injection rates between wells and causing steam channeling between wells during steam stimulation.

[0003] At present, research on the method of splitting the steam injection rate between different layers of steam huff-and-puff wells in multi-layer commingled heavy oil reservoirs mainly focuses on the characterization and dynamic identification of steam channeling channels. However, there is little research on the method of splitting the steam injection rate between layers and wells during steam huff-and-puff, and there is currently no specific determination method. Summary of the Invention

[0004] The present invention is proposed to solve the problem in the prior art that it is difficult to determine the steam absorption amount of steam injected between layers and wells during steam stimulation. Its purpose is to provide a method for splitting the steam injection amount in different layers of steam stimulation wells in multi-layer commingled heavy oil reservoirs.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for splitting steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir comprises the following steps:

[0007] S1. Obtain steam injection parameters of the target oilfield well group;

[0008] S2. Obtaining geological reservoir parameters of each layer of the target reservoir based on well logging data;

[0009] S3. Calculate the steam splitting coefficient and steam absorption capacity between target reservoir layers;

[0010] S4. Obtain basic inter-well geological reservoir parameters within each sub-layer of the target oil layer based on the well location data;

[0011] S5. Calculate the average formation coefficient between the steam injection well and the steam channeling well in the target oil reservoir;

[0012] S6. Calculate the splitting angle between the steam injection well and each steam channeling well in the target oil reservoir;

[0013] S7. Calculate the splitting coefficient and steam absorption volume between the target oil reservoir's steam injection well and each steam channeling well.

[0014] In the above technical solution, the steam injection parameters include steam temperature, steam pressure, steam injection flow rate and steam injection quality.

[0015] In the above technical solution, the geological reservoir parameters include permeability and oil layer thickness.

[0016] In the above technical solution, the method for calculating the steam splitting coefficient and steam absorption capacity between layers of the target reservoir in step S3 is specifically as follows: based on the geological reservoir parameters between different layers of the target reservoir obtained in S2, according to the formation factor distribution method, the steam splitting coefficient between each layer is calculated using the steam splitting coefficient formula, and the steam absorption capacity of each layer is calculated using the steam absorption capacity formula:

[0017] The steam splitting coefficient formula is:

[0018]

[0019] Where: δ j is the interlayer steam splitting coefficient of layer j, dimensionless; K j is the permeability of the jth layer, in mD; h j is the oil layer thickness of the jth sublayer, in meters; Z is the total number of sublayers in the oil layer, dimensionless;

[0020] The steam inhalation formula is:

[0021] i s,j =I·δ j (2)

[0022] Where: i s,j is the steam suction volume of the jth layer, in t / d; I is the total steam injection volume, in t / d; δ j is the interlayer steam splitting coefficient of layer j, dimensionless.

[0023] In the above technical solution, the basic inter-well geological reservoir parameters within each sub-layer of the target oil layer in step S4 include the well spacing between the steam injection well and the steam channeling well, the well spacing between the steam channeling well and the steam channeling well, the average permeability between the steam injection well and the steam channeling well, and the average oil layer thickness between the steam injection well and the steam channeling well.

[0024] The calculation method of the basic parameters of the inter-well geological reservoir in each sub-layer of the target oil layer is specifically as follows:

[0025] Based on the well location coordinate data of the target well group, a well location relationship diagram of the target block is drawn, and the well spacing between the steam injection wells and the steam channeling wells, as well as the well spacing between the steam channeling wells, is determined using formula (3). Combined with the distribution characteristics of the reservoir physical properties between the steam injection wells and the steam channeling wells in the target well group, the average permeability between the steam injection wells and the steam channeling wells is calculated using formula (4), and the average oil layer thickness between the steam injection wells and the steam channeling wells is calculated using formula (5):

[0026]

[0027] Where: d is the well spacing, unit is m; x1, y1 are the coordinates of the steam injection well or steam channeling well, dimensionless; x2, y2 are the coordinates of the steam injection well or steam channeling well, dimensionless; is the average permeability of the steam injection well in the jth layer from the steam channeling well i, in mD; is the average oil layer thickness from the steam injection well in layer j to the steam channeling well i, in meters; K i,j,k is the permeability value between the steam injection well in layer j and the steam channeling well i, in mD; h i,j,k is the oil layer thickness between the steam injection well in layer j and the channeling well i, in meters. N is the dimensionless number of different permeability and oil layer thickness values ​​between the steam injection well j and channeling well i. Due to the heterogeneity of reservoir properties (permeability and oil layer thickness) between the steam injection well and the channeling well, the permeability and oil layer thickness values ​​vary between wells. Since the average permeability and average oil layer thickness are calculated, the number of different parameter values ​​must be specified to calculate the average.

[0028] In the above technical solution, the method for calculating the average formation coefficient between the steam injection well and the steam channeling well in the target oil reservoir in step S5 is specifically as follows: based on the average permeability between the steam injection well and the steam channeling well and the average oil layer thickness between the steam injection well and the steam channeling well obtained in S4, the average formation coefficient between the steam injection well and the steam channeling well is calculated using formula (6):

[0029]

[0030] Where: is the average formation coefficient of the distance between the steam injection well in the jth layer and the steam channeling well i, in mD·m; is the average permeability of the steam injection well in the jth layer from the steam channeling well i, in mD; is the average oil layer thickness from the steam injection well in layer j to the steam channeling well i, in meters.

[0031] In the above technical solution, the method for calculating the splitting angle between the target oil reservoir steam injection well and each steam channeling well in step S6 is specifically as follows:

[0032] Based on the well location relationship diagram in step S4, the well spacing between the steam injection well and the steam channeling well, and the well spacing parameters between the steam channeling well and the steam channeling well, the circular heating radius of the steam channeling well is calculated based on the calculation method (7) of the steam channeling process heating range in the Marx-Langenheim heating theory. By analyzing the position and connectivity relationship between the steam injection well and the steam channeling well, the splitting angle of each well is determined using formulas (8), (9), (10), (11), (12), and (13).

[0033]

[0034]

[0035] in,

[0036]

[0037] Where: r s is the heating radius of the steam chamber, in m; i s is the steam injection rate, in kg / s; x is the injected steam quality, in decimals; L v is the latent heat of vaporization of steam, in J / kg; M R is the volume heat capacity of the oil layer, in J / (m 3 ·℃); h is the oil layer thickness, in m; α s is the thermal diffusivity of the top and bottom cover layers, in m 2 / s;λ r is the thermal conductivity of the top and bottom layers, in W / (m·℃); T s is the steam temperature, in °C; T i is the initial temperature of the oil layer, in °C; t D is dimensionless time, a decimal; ω j,i is the splitting angle corresponding to the steam channeling well i in the jth layer, in degrees; θ j,i θ is the angle between the tangent point of the heating circle of the steam channeling well i and the steam injection well in the jth layer and the line connecting the steam injection well, in degrees; j,i-1 θ is the angle between the tangent point of the steam channeling well i-1 in the jth layer and the heating circle of the steam injection well and the line connecting the steam injection well, in degrees; j,i+1 β is the angle between the tangent point of the steam channeling well i+1 in the jth layer and the heating circle of the steam injection well and the line connecting the steam injection well, in degrees; j,i-1,i β is the angle between the right tangent point of the steam channeling well i-1 and the steam injection well heating circle in the jth layer and the line connecting the steam injection well and the left tangent point of the steam channeling well i and the steam injection well heating circle, in degrees; j,i,i+1 ξ is the angle between the line connecting the right tangent point of the heating circle of the steam channeling well i and the steam injection well in the jth layer and the line connecting the left tangent point of the heating circle of the steam channeling well i+1 and the steam injection well, in degrees;j,i-1,i ξ is the angle between the line connecting the steam channeling well i-1 in the j-th layer and the steam injection well and the line connecting the steam channeling well i in the j-th layer and the steam injection well, in degrees; j,i,i+1 L is the angle between the line connecting the steam channeling well i and the steam injection well in the jth layer and the line connecting the steam channeling well i+1 and the steam injection well in the jth layer, in degrees; j,i-1 is the distance between well i-1 and the steam injection well in layer j, in meters; L j,i is the distance between well i and the steam injection well in layer j, in meters; L j,i+1 is the distance between well i+1 and the steam injection well in layer j, in meters; L j,i-1,i is the distance between well i-1 and well i in layer j, in meters; L j,i,i+1 It is the distance between well i and well i+1 in layer j, in meters.

[0038] In the above technical solution, the method for calculating the splitting coefficient and steam absorption amount between the steam injection well and each steam channeling well in the target oil reservoir in step S7 is as follows: Based on the relevant parameters between the steam injection well and each steam channeling well obtained in step S6, the splitting coefficient and splitting amount between the steam injection well and each steam channeling well are calculated using formula (14) and formula (15):

[0039]

[0040] Where: c j,i is the splitting coefficient corresponding to the steam channeling well i in the j layer, a decimal; i s,j,i is the steam suction volume corresponding to the well i in the j-th layer, in t / d.

[0041] The beneficial effects of the present invention are:

[0042] The present invention provides a method for splitting the steam injection rate in different layers of a steam huff and puff well in a multi-layer commingled production heavy oil reservoir. The method can determine the steam injection rate and steam intake rate between layers and between wells during the steam huff and puff process, and provides a basis for determining the reasonable steam injection rate during the steam huff and puff process in a heavy oil thermal recovery oilfield. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a flow chart of the method of the present invention;

[0044] Figure 2 Schematic diagram of the difference in gas injection volume between layers of a multi-layer reservoir in Example 1 of the present invention;

[0045] Figure 3 Schematic diagram of the relative positions and well spacing between steam stimulation well A and the steam channeling well in Example 1 of the present invention;

[0046] Figure 4 Schematic diagram of the relationship between the steam stimulation well A and the steam channeling well at various angles in Example 1 of the present invention.

[0047] For ordinary technicians in this field, other relevant drawings can be obtained based on the above drawings without any creative work. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.

[0049] Example 1

[0050] A method for splitting the steam injection rate between different layers of a steam huff and puff well in a multi-layer commingled production heavy oil reservoir is proposed. Taking a certain huff and puff well group as an example, the method determines the steam injection rate splitting coefficients between the layers and wells of the well group during the steam huff and puff process in accordance with the steps, thereby determining the steam intake between the layers and wells during the steam huff and puff process in the heavy oil reservoir.

[0051] like Figure 1 As shown, a method for splitting the steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled heavy oil reservoir comprises the following steps:

[0052] S1. Obtain steam injection parameters of the target oilfield well group.

[0053] Based on actual production operations, the steam injection parameters during the steam stimulation process of the target block well group were statistically analyzed, including basic parameters such as steam temperature, steam pressure, steam injection flow rate, and steam injection dryness, as shown in Table 1.

[0054] Table 1 Statistics of dynamic data of steam injection wells

[0055]

[0056] S2. Obtain geological reservoir parameters of each layer of the target reservoir based on well logging data.

[0057] In multi-layered heavy oil reservoirs, oil layers are separated by impermeable barriers, e.g. Figure 2 As shown in Figure 2, during steam injection, due to differences in reservoir properties between layers, the amount of injected steam absorbed will vary. Based on well logging data, geological reservoir parameters for each layer of the target reservoir are obtained, including permeability and reservoir thickness. Permeability and reservoir thickness values ​​are shown in Table 2.

[0058] Table 2 Statistics of geological reservoir parameters between layers of multilayer reservoir in Well A

[0059]

[0060] S3. Calculate the steam splitting coefficient and steam absorption capacity between target reservoir layers:

[0061] Due to the differences in permeability between thin layers, based on the geological reservoir parameters of different layers of the target reservoir obtained in S2 and according to the formation factor distribution method, the steam splitting coefficient of each layer can be calculated using formula (1), and the steam absorption capacity of each layer can be calculated using formula (2), as shown in Table 3.

[0062]

[0063] isj=I·δj(2)

[0064] Where is,j is the steam intake of the jth layer, in t / d; I is the total steam injection rate, in t / d; δj is the interlayer steam splitting coefficient of the jth layer, in decimals; Kj is the permeability of the jth sublayer, in mD; h j is the oil layer thickness of the jth sublayer, in meters; Z is the total number of sublayers in the oil layer, dimensionless.

[0065] Table 3 Interlayer steam splitting coefficient and steam absorption volume of Well A

[0066]

[0067] S4. Based on the well location data, obtain the basic parameters of the inter-well geological reservoir in each sub-layer of the target oil layer.

[0068] Based on the target well group well location coordinate data, the target block well location relationship diagram is drawn, and the well spacing between the steam injection well and the steam channeling well, and the well spacing between the steam channeling well and the steam channeling well are determined using formula (3); the well coordinate data are shown in Table 4, and the well location relationship diagram is shown in Figure 3 , the well spacing is shown in Table 5.

[0069] Based on the distribution characteristics of reservoir physical properties between the steam injection wells and the steam channeling wells in the target well group, the average permeability between the steam injection wells and the steam channeling wells was calculated using formula (4), and the average oil layer thickness between the steam injection wells and the steam channeling wells was calculated using formula (5). The average permeability and average oil layer thickness between the steam injection wells and the steam channeling wells are shown in Table 6.

[0070]

[0071] Where: d is the well spacing, unit is m; x1, y1 are the coordinates of the steam injection well or steam channeling well, dimensionless; x2, y2 are the coordinates of the steam injection well or steam channeling well, dimensionless; is the average permeability of the steam injection well in the jth layer from the steam channeling well i, in mD; is the average oil layer thickness from the steam injection well in layer j to the steam channeling well i, in meters; K i,j,k is the permeability value between the steam injection well in layer j and the steam channeling well i, in mD; h i,j,kis the oil layer thickness between the steam injection well in the jth layer and the steam channeling well i, in meters; N is the number of different values ​​of permeability and oil layer thickness between the steam injection well in the jth layer and the steam channeling well i, dimensionless.

[0072] Table 4. Well location coordinate data of target well group

[0073] well name Well point coordinates A (116.471,-111.937) B1 (21.568,-157.339) B2 (182.745,-117.417) B3 (26.275,-69.667)

[0074] Table 5 Statistics of target well group spacing

[0075]

[0076] Table 6 Calculation results of average permeability and average oil layer thickness among target well groups

[0077]

[0078] S5. Calculate the average formation coefficient between the steam injection well and the steam channeling well in the target oil reservoir.

[0079] Based on the average permeability and average oil layer thickness between the steam injection well and the steam channeling well obtained in S4, the average formation coefficient between the steam injection well and the steam channeling well was calculated using formula (6). The calculated results of the average formation coefficient are shown in Table 7.

[0080]

[0081] Where: is the average formation coefficient of the distance between the steam injection well in the jth layer and the steam channeling well i, in mD·m; is the average permeability of the steam injection well in the jth layer from the steam channeling well i, in mD; is the average oil layer thickness from the steam injection well in layer j to the steam channeling well i, in meters.

[0082] Table 7 Calculation results of average formation coefficient among target well groups

[0083]

[0084] S6. Calculate the splitting angle between the target reservoir's steam injection well and each steam channeling well.

[0085] Based on the well location relationship diagram in step S4, the well spacing between the steam injection well and the steam channeling well, and the well spacing parameters between the steam channeling well and the steam channeling well, and on the basis of calculating the circular heating radius of the steam channeling well based on the steam flow process heating range calculation formula (7) in the Marx-Langenheim heating theory, by analyzing the position and connectivity relationship between the steam injection well and the steam channeling well, the splitting angle of each well can be determined using formulas (8), (9), (10), (11), (12) and (13). Taking the relationship between the wells in the third layer as an example, as Figure 4 The heating cavity radius is shown in Table 8 and the connection relationships are shown in Table 9. The Marx-Langenheim heating theory is based on the literature Marx JW, Langenheim RH. Reservoir heating by hot fluid injection [J]. Transactions of the AIME, 1959, 216(01): 312-315.

[0086]

[0087] in,

[0088]

[0089] Where: r s is the heating radius of the steam chamber, in m; i s is the steam injection rate, in kg / s; x is the injected steam quality, in decimals; L v is the latent heat of vaporization of steam, in J / kg; M R is the volume heat capacity of the oil layer, in J / (m 3 ·℃); h is the oil layer thickness, in m; α s is the thermal diffusivity of the top and bottom cover layers, in m 2 / s;λ r is the thermal conductivity of the top and bottom layers, in W / (m·℃); T s is the steam temperature, in °C; T i is the initial temperature of the oil layer, in °C; t D is dimensionless time, a decimal; ω j,i is the splitting angle corresponding to the steam channeling well i in the jth layer, in degrees; θ j,i θ is the angle between the tangent point of the heating circle of the steam channeling well i and the steam injection well in the jth layer and the line connecting the steam injection well, in degrees; j,i-1 θ is the angle between the tangent point of the steam channeling well i-1 in the jth layer and the heating circle of the steam injection well and the line connecting the steam injection well, in degrees; j,i+1 β is the angle between the tangent point of the steam channeling well i+1 in the jth layer and the heating circle of the steam injection well and the line connecting the steam injection well, in degrees;j,i-1,i β is the angle between the right tangent point of the steam channeling well i-1 and the steam injection well heating circle in the jth layer and the line connecting the steam injection well and the left tangent point of the steam channeling well i and the steam injection well heating circle, in degrees; j,i,i+1 ξ is the angle between the line connecting the right tangent point of the heating circle of the steam channeling well i and the steam injection well in the jth layer and the line connecting the left tangent point of the heating circle of the steam channeling well i+1 and the steam injection well, in degrees; j,i-1,i ξ is the angle between the line connecting the steam channeling well i-1 in the j-th layer and the steam injection well and the line connecting the steam channeling well i in the j-th layer and the steam injection well, in degrees; j,i,i+1 L is the angle between the line connecting the steam channeling well i and the steam injection well in the jth layer and the line connecting the steam channeling well i+1 and the steam injection well in the jth layer, in degrees; j,i-1 is the distance between well i-1 and the steam injection well in layer j, in meters; L j,i is the distance between well i and the steam injection well in layer j, in meters; L j,i+1 is the distance between well i+1 and the steam injection well in layer j, in meters; L j,i-1,i is the distance between well i-1 and well i in layer j, in meters; L j,i,i+1 It is the distance between well i and well i+1 in layer j, in meters.

[0090] Table 8 Steam stimulation A well 3 small layer heating cavity radius

[0091] parameter Value <![CDATA[r s ]]> 30.00

[0092] Table 9 Connectivity relationship of the three sub-layers in Well A during steam stimulation

[0093] parameter Value parameter Value parameter Value parameter Value <![CDATA[θ 3,1 ]]> 155.81 <![CDATA[ξ 3,1,2 ]]> 116.66 <![CDATA[β 3,1,2 ]]> 35.28 <![CDATA[ω 3,1 ]]> 139.77 <![CDATA[θ 3,2 ]]> 148.08 <![CDATA[ξ 3,2,3 ]]> 93.37 <![CDATA[β 3,2,3 ]]> 50.89 <![CDATA[ω 3,2 ]]> 104.99 <![CDATA[θ 3,3 ]]> 140.43 <![CDATA[ξ 3,3,1 ]]> 151.32 <![CDATA[β 3,3,1 ]]> 0.00 <![CDATA[ω 3,3 ]]> 114.99

[0094] S7. Calculate the splitting coefficient and steam absorption volume between the target oil reservoir's steam injection well and each steam channeling well.

[0095] Based on the relevant parameters between the steam injection well and each steam channeling well obtained in step S6, the splitting coefficient and splitting amount between the steam injection well and each steam channeling well can be calculated using formulas (14) and (15). An example is shown in Table 10.

[0096]

[0097] i sj,i =c j,i ·i sj (15)

[0098] Where: c j,i is the splitting coefficient corresponding to the steam channeling well i in the jth layer, dimensionless; i s,j,i is the steam suction volume corresponding to the well i in the j-th layer, in t / d.

[0099] Table 10 Steam stimulation A well 3 sub-layer steam splitting coefficient and steam splitting amount

[0100]

[0101] The present invention first calculates the steam splitting coefficient and steam absorption capacity between target reservoir layers based on the obtained steam injection parameters of the target oil field well group and the determined basic geological reservoir parameters between target reservoir layers; based on the determined steam absorption capacity of each layer, by determining the basic geological reservoir parameters between wells in each small layer of the target oil layer, the average geological coefficient between the target steam injection well and the steam channeling well can be calculated; then, combined with parameters such as the well spacing between the target well groups, the splitting angle between the target oil reservoir steam injection well and each steam channeling well can be calculated; finally, the splitting coefficient and steam absorption capacity between the target oil reservoir steam injection well and each steam channeling well can be calculated.

[0102] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A method for splitting the steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir, characterized by: The following steps are involved: S1. Obtain steam injection parameters of the target oilfield well group; S2. Obtaining geological reservoir parameters of each layer of the target reservoir based on well logging data; S3. Calculate the steam splitting coefficient and steam absorption capacity between target reservoir layers; S4. Obtain basic inter-well geological reservoir parameters within each sub-layer of the target oil layer based on the well location data; S5. Calculate the average formation coefficient between the steam injection well and the steam channeling well in the target oil reservoir; S6. Calculate the splitting angle between the steam injection well and each steam channeling well in the target oil reservoir; The calculation method of the splitting angle between the target reservoir steam injection well and each steam channeling well is as follows: Based on the well location relationship diagram in step S4, the well spacing between the steam injection well and the steam channeling well, and the well spacing parameters between the steam channeling well and the steam channeling well, the circular heating radius of the steam channeling well is calculated based on the calculation method (7) of the steam channeling process heating range in the Marx-Langenheim heating theory. By analyzing the position and connectivity relationship between the steam injection well and the steam channeling well, the splitting angle of each well is determined using formulas (8), (9), (10), (11), (12), and (13). in, Where: r s is the heating radius of the steam chamber, in m; i s is the steam injection rate, in kg / s; x is the injected steam quality, in decimals; L v is the latent heat of vaporization of steam, in J / kg; M R is the volume heat capacity of the oil layer, in J / (m 3 ·℃); h is the oil layer thickness, in m; α s is the thermal diffusivity of the top and bottom cover layers, in m 2 / s;λ r is the thermal conductivity of the top and bottom layers, in W / (m·℃); T s is the steam temperature, in °C; T i is the initial temperature of the oil layer, in °C; t D is dimensionless time, a decimal; ω j,i is the splitting angle corresponding to the steam channeling well i in the jth layer, in degrees; θ j,i θ is the angle between the tangent point of the heating circle of the steam channeling well i and the steam injection well in the jth layer and the line connecting the steam injection well, in degrees; j,i-1 θ is the angle between the tangent point of the steam channeling well i-1 in the jth layer and the heating circle of the steam injection well and the line connecting the steam injection well, in degrees; j,i+1 β is the angle between the tangent point of the steam channeling well i+1 in the jth layer and the heating circle of the steam injection well and the line connecting the steam injection well, in degrees; j,i-1,i β is the angle between the right tangent point of the steam channeling well i-1 and the steam injection well heating circle in the jth layer and the line connecting the steam injection well and the left tangent point of the steam channeling well i and the steam injection well heating circle, in degrees; j,i,i+1 ξ is the angle between the line connecting the right tangent point of the heating circle of the steam channeling well i and the steam injection well in the jth layer and the line connecting the left tangent point of the heating circle of the steam channeling well i+1 and the steam injection well, in degrees; j,i-1,i ξ is the angle between the line connecting the steam channeling well i-1 in the j-th layer and the steam injection well and the line connecting the steam channeling well i in the j-th layer and the steam injection well, in degrees; j,i,i+1 L is the angle between the line connecting the steam channeling well i and the steam injection well in the jth layer and the line connecting the steam channeling well i+1 and the steam injection well in the jth layer, in degrees; j,i-1 is the distance between well i-1 and the steam injection well in layer j, in meters; L j,i is the distance between well i and the steam injection well in layer j, in meters; L j,i+1 is the distance between well i+1 and the steam injection well in layer j, in meters; L j,i-1,i is the distance between well i-1 and well i in layer j, in meters; L j,i,i+1 Then it is the distance between well i and well i+1 in layer j, in meters; S7. Calculate the splitting coefficient and steam absorption volume between the target oil reservoir's steam injection well and each steam channeling well; The specific method for calculating the splitting coefficient and steam absorption amount between the steam injection well and each steam channeling well in the target oil reservoir is as follows: Based on the relevant parameters between the steam injection well and each steam channeling well obtained in step S6, the splitting coefficient and splitting amount between the steam injection well and each steam channeling well are calculated using formula (14) and formula (15): i s,j,i =c j,i ·i s,j (15) Where: c j,i is the splitting coefficient corresponding to the steam channeling well i in the jth layer, a decimal; i s,j,i is the steam suction volume corresponding to the well i in the jth layer, in t / d; i s,j is the steam suction volume of the jth layer, in t / d; is the average formation coefficient of the distance between the steam injection well in the jth layer and the steam channeling well i, in mD·m.

2. The method for splitting steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir according to claim 1, characterized in that: The steam injection parameters include steam temperature, steam pressure, steam injection flow rate and steam injection quality.

3. The method for splitting steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir according to claim 1, characterized in that: The geological reservoir parameters include permeability and oil layer thickness.

4. The method for splitting steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir according to claim 1, characterized in that: The method for calculating the steam splitting coefficient and steam absorption volume between layers of the target reservoir in step S3 is as follows: based on the geological reservoir parameters between different layers of the target reservoir obtained in S2, according to the formation factor distribution method, the steam splitting coefficient between each layer is calculated using the steam splitting coefficient formula, and the steam absorption volume of each layer is calculated using the steam absorption volume formula: The steam splitting coefficient formula is: Where: δ j is the interlayer steam splitting coefficient of layer j, dimensionless; K j is the permeability of the jth layer, in mD; h j is the oil layer thickness of the jth sublayer, in meters; Z is the total number of sublayers in the oil layer, dimensionless; The calculation formula for the steam intake is: i s,j =I·δ j (2) Where: i s,j is the steam suction volume of the jth layer, in t / d; I is the total steam injection volume, in t / d; δ j is the interlayer steam splitting coefficient of layer j, dimensionless.

5. The method for splitting steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir according to claim 1, characterized in that: The basic parameters of the inter-well geological reservoir in each sub-layer of the target oil layer in step S4 include the well spacing between the steam injection well and the steam channeling well, the well spacing between the steam channeling well and the steam channeling well, the average permeability between the steam injection well and the steam channeling well, and the average oil layer thickness between the steam injection well and the steam channeling well; The calculation method of the basic parameters of the inter-well geological reservoir in each sub-layer of the target oil layer is specifically as follows: Based on the well location coordinate data of the target well group, a well location relationship diagram of the target block is drawn, and the well spacing between the steam injection wells and the steam channeling wells, as well as the well spacing between the steam channeling wells, is determined using formula (3). Combined with the distribution characteristics of the reservoir physical properties between the steam injection wells and the steam channeling wells in the target well group, the average permeability between the steam injection wells and the steam channeling wells is calculated using formula (4), and the average oil layer thickness between the steam injection wells and the steam channeling wells is calculated using formula (5): Where: d is the well spacing, unit is m; x1, y1 are the coordinates of the steam injection well or steam channeling well, dimensionless; x2, y2 are the coordinates of the steam injection well or steam channeling well, dimensionless; is the average permeability of the steam injection well in the jth layer from the steam channeling well i, in mD; is the average oil layer thickness from the steam injection well in layer j to the steam channeling well i, in meters; K i,j,k is the permeability value between the steam injection well in layer j and the steam channeling well i, in mD; h i,j,k The thickness of the oil layer between the steam injection well in layer j and the steam channeling well i is measured in meters; N is the number of different values ​​of permeability and oil layer thickness between the steam injection well in layer j and the steam channeling well i, which is dimensionless.

6. The method for splitting steam injection rate in different layers of a steam huff-and-puff well in a multi-layer commingled production heavy oil reservoir according to claim 1, characterized in that: The method for calculating the average formation coefficient between the steam injection well and the steam channeling well in step S5 is as follows: based on the basic geological reservoir parameters between the wells in each sub-layer of the target oil layer obtained in S4, the average formation coefficient between the steam injection well and the steam channeling well is calculated using formula (6): Where: is the average formation coefficient of the distance between the steam injection well in the jth layer and the steam channeling well i, in mD·m; is the average permeability of the steam injection well in the jth layer from the steam channeling well i, in mD; is the average oil layer thickness from the steam injection well in layer j to the steam channeling well i, in meters.

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