Method for calculating fluid production capacity of multi-layer commingled reservoir

Abstract

The present application relates to the technical field of oilfield development, in particular to a kind of liquid production capacity calculation method of multilayer commingling reservoir, obtain the bottom hole flowing pressure and liquid production index when each oil layer is separately produced;Pressure loss of fluid flowing in wellbore and interlayer flow pressure difference when adjacent two oil layers are separately produced are calculated;The difference between the bottom hole flowing pressure of oil layer 2 and oil layer 1 when the reservoir is separately produced and the size of the pressure loss of fluid flowing in wellbore are compared, to obtain the remaining start-up pressure of the disturbed oil layer when two oil layers are commingled;According to the remaining start-up pressure, the corrected liquid production index of the disturbed oil layer is obtained;According to the liquid production index model of two-layer commingling, the corrected liquid production index of the disturbed oil layer when multilayer commingling is obtained;The sum of the liquid production index of each oil layer is the total liquid production index of the oil well.

Description

Technical Field

[0001] This invention relates to the field of oilfield development technology, and specifically to a method for calculating the fluid production capacity of multi-layered syngas reservoirs. Background Technology

[0002] Yanchang Oilfield is located in the southeastern part of the Ordos Basin. Among them, the superimposed sandstone reservoirs in the western part of Yanchang Oilfield are relatively well-developed. However, in the process of developing superimposed sandstone reservoirs, there are large differences in the physical and fluid properties of each layer in the vertical direction, and the inter-layer interference is serious. It is impossible to accurately divide the fluid production index of multi-layer synergistic oil wells, conduct dynamic analysis of oil wells, and determine the reasonable working system of oil wells.

[0003] Determining the fluid production capacity of multi-layered sandstone reservoirs hinges on the fluid production index calculation model. Current single-layer reservoir fluid production index models are limited to calculating the fluid production index during single-layer reservoir production. Furthermore, they consider relatively simple parameters, have complex acquisition processes, and low accuracy, failing to reflect the fluid seepage characteristics and are not suitable for calculating the fluid production index of each layer in multi-layered multi-layered reservoirs.

[0004] To determine the fluid production index of each layer in a multi-layered, multi-layered oil reservoir, this invention, based on two-phase flow theory and fluid mechanics, considers the influence of parameters such as formation pressure, starting pressure gradient, effective layer thickness, crude oil viscosity, and permeability. It also considers the frictional effect of fluid flow within the wellbore and the pressure drop caused by gravity. This results in a fluid flow pressure drop prediction model within the wellbore and a fluid production index model for multi-layered development in stacked sandstone reservoirs. This method not only calculates the fluid production index of each layer in a multi-layered development well in a stacked reservoir but also considers a comprehensive range of parameters, offers fast calculation speed, and high accuracy. By comparing the fluid production index of each layer in multi-layered development with that of a single-layer production well, the interference coefficient of each layer can be obtained. The magnitude of the interference coefficient can be used to determine the intensity of interference experienced by each layer during multi-layered development in a stacked reservoir. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a method for calculating the fluid production capacity of multi-layered syngas reservoirs.

[0006] The technical solution of this invention is as follows:

[0007] A method for calculating the fluid production capacity of multi-layered syngas reservoirs is as follows: Obtain the bottomhole flowing pressure and fluid production index when each oil layer is producing independently; Calculate the pressure loss of fluid flowing in the wellbore and the flow pressure difference between two adjacent oil layers when they are producing independently; By comparing the bottom-hole pressure difference between oil layer 2 and oil layer 1 when the reservoir is produced alone with the pressure loss of fluid flowing in the wellbore, the remaining starting pressure of the disturbed oil layer when the two oil layers are produced together can be obtained. The corrected fluid production index of the disturbed oil layer is obtained based on the remaining start-up pressure. The corrected fluid production index of the disturbed oil layer in multi-layer combined production is obtained based on the two-layer combined production fluid production index model. The sum of the production indices of each oil layer is the total production index of the oil well.

[0008] The bottom hole flowing pressure when each oil layer is producing independently is: (1) The fluid recovery index when each oil layer is producing independently is: (2) In the formula: The bottomhole flowing pressure when the oil reservoir is producing independently; is the fluid viscosity, mPa·s; B is the volume coefficient, dimensionless. The supply radius is in meters (m). Let be the radius of the wellbore, in meters (m). Where is the diameter of the wellbore, in meters (m). For fluid density, 10 3 kg / m 3 ; For the effective permeability of the oil reservoir, 10 -3 μm 3 ; The effective thickness of the oil layer is in meters (m). G is the formation pressure, MPa; G is the starting pressure gradient, MPa / m. The fluid collection index, m 3 / d·MPa.

[0009] The pressure loss of the fluid flowing inside the wellbore is: (3) When two oil layers are produced separately, the interlayer flow pressure difference is: (4) In the formula: The pressure loss caused by fluid flow within the wellbore, expressed in MPa. The acceleration due to gravity is m / s². 2 ; The vertical distance between oil layers, in meters (m). The pressure difference between the two oil layers during individual production, in MPa; The bottomhole flowing pressure (MPa) is the pressure when oil layer 2 is producing alone. The bottomhole flowing pressure (MPa) is the pressure when oil layer 1 is producing alone. For the effective permeability of oil layer 2, 10 -3 μm3 ; The effective thickness of oil layer 2 is in meters. The formation pressure of oil layer 2 is MPa; The starting pressure gradient for oil layer 2 is MPa / m; Provide a radius (m) for oil layer 2; The viscosity of the fluid in layer 2 is mPa·s; The volume factor for oil layer 2; The effective permeability of oil layer 1, 10 -3 μm 3 ; The effective thickness of oil layer 1 is in meters (m). The formation pressure of oil layer 1 is MPa; The starting pressure gradient for oil layer 1 is MPa / m; Provide a radius of m for oil layer 1; The viscosity of the fluid in oil layer 1 is given in mPa·s. This is the volume factor for oil layer 1.

[0010] The specific process for obtaining the remaining starting pressure of the disturbed oil layer during the combined production of the two oil layers is as follows: When two oil layers are produced together, if At that time, there is no interference between the oil layers, and the fluid production capacity remains unchanged; if At that time, there is inter-layer interference between oil layers, and the fluid production capacity changes. when At that time, there is no interlayer interference in oil layer 2, and the fluid flow within oil layer 2 has no additional pressure drop; there is interlayer interference in oil layer 1, and the fluid flow within oil layer 1 has an additional pressure drop. Its remaining starting pressure is: (5) when At that time, there is no interlayer interference in oil layer 1, and the fluid flow within oil layer 1 has no additional pressure drop; there is interlayer interference in oil layer 2, and the fluid flow within oil layer 2 has an additional pressure drop. Its remaining starting pressure is: (6) In the formula: The remaining starting pressure of oil layer 1 is MPa; The remaining starting pressure of oil layer 2 is MPa.

[0011] The corrected fluid production index of the disturbed oil layer is: when At that time, interlayer interference existed in oil layer 1, and the fluid flow within oil layer 1 resulted in an additional pressure drop. The corrected production fluid index for oil layer 1 was: (7) when At that time, interlayer interference existed in oil layer 2, and the fluid flow within oil layer 2 resulted in an additional pressure drop. The corrected production index for oil layer 2 was: (8) In the formula: The corrected production index for reservoir 1, m 3 / d·MPa; The corrected production index for reservoir 2, m 3 / d·MPa.

[0012] The specific solution process for the corrected production fluid index of the disturbed oil layer during multi-layer synergistic production is as follows: In the formula: The corrected production index for reservoir 1, m 3 / d·MPa; The effective permeability of oil layer 1, 10 -3 μm 3 ; The effective thickness of oil layer 1 is in meters (m). The viscosity of the fluid in layer 2 is mPa·s; The volume factor for oil layer 2; Provide a radius (m) for oil layer 2; Let be the radius of the wellbore, in meters (m). For fluid density, 10 3 kg / m 3 ; The formation pressure of oil layer 1 is MPa; The starting pressure gradient for oil layer 1 is MPa / m; Provide a radius of m for oil layer 1; The viscosity of the fluid in oil layer 1 is given in mPa·s. The volume factor for oil layer 1; For the effective permeability of oil layer 2, 10 -3 μm 3 ; The effective thickness of oil layer 2 is in meters. The formation pressure of oil layer 2 is MPa; oil layer Corrected liquid collection index, m 3 / d·MPa; For the effective permeability of the oil reservoir j, 10 -3 μm 3 ; oil layer Effective thickness, m; oil layer Fluid viscosity, mPa·s; oil layer Volume index; oil layer Supply radius, m; oil layer Formation pressure, MPa; oil layer Initiate pressure gradient, MPa / m; Oil layer during single-layer production Bottom hole flowing pressure, MPa; Oil layer during single-layer production Bottom hole flowing pressure, MPa; For fluid from the oil layer Flow to the oil layer The total pressure drop during flow, MPa.

[0013] The specific solution process for the total fluid production index is as follows: (10) In the formula: The total fluid production index, m 3 / d·MPa; The corrected production index for reservoir 2, m 3 / d·MPa; oil layer Corrected liquid collection index, m 3 / d·MPa.

[0014] The technical advantages of this invention are as follows: This invention provides a method for calculating the fluid production index of multi-layered synergistic oil reservoirs. Based on this method, the fluid production capacity of each oil layer in a multi-layered synergistic oil reservoir can be obtained, and the total fluid production capacity after synergistic production of each oil layer in an oil well can be determined. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of oil well production in a superimposed sandstone reservoir according to the present invention.

[0016] Figure 2 This is a comparison chart of the calculated and actual tested fluid production index values ​​when oil layer 1 is produced alone according to the present invention.

[0017] Figure 3 This is a comparison chart of the calculated and actual tested fluid production index values ​​when oil layer 2 is produced independently according to the present invention.

[0018] Figure 4 This is a comparison chart of the calculated and actual tested fluid production index values ​​when oil layer 3 is produced independently according to the present invention.

[0019] Figure 5This is a comparison chart of the calculated and actual tested fluid production index values ​​for oil layer 1 in the multi-layered synergistic oil reservoir of the present invention.

[0020] Figure 6 This is a comparison chart of the calculated and actual tested fluid production index values ​​for the oil layer 2 of the multi-layered synergistic oil reservoir of the present invention.

[0021] Figure 7 This is a comparison chart of the calculated and actual tested fluid production index values ​​for the oil layer 3 of the multi-layered synergistic oil reservoir of the present invention. Detailed Implementation

[0022] Example 1 – A method for calculating the fluid production capacity of multi-layered syngas reservoirs, the method is as follows: Obtain the bottomhole flowing pressure and fluid production index when each oil layer is producing independently; Calculate the pressure loss of fluid flowing in the wellbore and the flow pressure difference between two adjacent oil layers when they are producing independently; By comparing the bottom-hole pressure difference between oil layer 2 and oil layer 1 when the reservoir is produced alone with the pressure loss of fluid flowing in the wellbore, the remaining starting pressure of the disturbed oil layer when the two oil layers are produced together can be obtained. The corrected fluid production index of the disturbed oil layer is obtained based on the remaining start-up pressure. The corrected fluid production index of the disturbed oil layer in multi-layer combined production is obtained based on the two-layer combined production fluid production index model. The sum of the production indices of each oil layer is the total production index of the oil well.

[0023] Example 2 – A method for calculating the fluid production capacity of a multi-layered syngas reservoir, the method is as follows:

[0024] Step 1: Obtain the bottomhole flowing pressure and fluid production index for each oil layer during individual production; specifically: The bottom hole flowing pressure when each oil layer is producing independently is calculated using formula (1); The fluid production index of each oil layer when it is produced individually is obtained by formula (2).

[0025] Step 2: Calculate the pressure loss of the fluid flowing in the wellbore and the flow pressure difference between two adjacent oil layers when they are producing independently; specifically: The pressure loss of fluid flowing in the wellbore is calculated using formula (3); The flow pressure difference between the two oil layers during individual production is calculated using formula (4).

[0026] Step 3: Compare the bottomhole flowing pressure difference between oil layer 2 and oil layer 1 when the reservoir is produced alone with the pressure loss of the fluid flowing in the wellbore to obtain the remaining starting pressure of the disturbed oil layer when the two oil layers are produced together; specifically: When two oil layers are produced together, if At that time, there is no interference between the oil layers, and the fluid production capacity remains unchanged; if At that time, there is inter-layer interference between oil layers, and the fluid production capacity changes. when At that time, there is no interlayer interference in oil layer 2, and there is no additional pressure drop in the fluid flow in oil layer 2; there is interlayer interference in oil layer 1, and there is an additional pressure drop in the fluid flow in oil layer 1. Its remaining starting pressure is calculated by formula (5). when At that time, there is no interlayer interference in oil layer 1 and no additional pressure drop in the fluid flow within oil layer 1; there is interlayer interference in oil layer 2 and an additional pressure drop in the fluid flow within oil layer 2. Its remaining starting pressure is calculated by formula (6).

[0027] Step 4: Obtain the corrected fluid production index of the disturbed oil layer based on the remaining start-up pressure; specifically: when At that time, there is interlayer interference in oil layer 1, and there is an additional pressure drop in the fluid flow in oil layer 1. The corrected production index of oil layer 1 is calculated by formula (7). when At that time, there is interlayer interference in oil layer 2, and there is an additional pressure drop in the fluid flow in oil layer 2. The corrected production index of oil layer 2 is calculated by formula (8).

[0028] Step 5: Obtain the corrected production index of the disturbed oil layer in multi-layer combined production based on the two-layer combined production fluid index model; see formula (9) for details.

[0029] Step 6: The sum of the production indices of each oil layer is the total production index of the oil well; see formula (10) for details.

[0030] Specific application case – A method for calculating the fluid production capacity of multi-layered syngas reservoirs, the method is as follows:

[0031] Step 1: Obtaining basic reservoir parameters: Field testing of formation pressure in different oil layers in a research area The starting pressure gradient of each oil layer was measured in an indoor (steady-state method) experiment. The effective thickness of each oil layer was obtained based on the lower limit standard of effective thickness in the study area. The effective permeability of each oil layer was obtained from core experiments and well test interpretation. Fluid density was obtained by PVT experimental analysis. Viscosity and volume factor The well grid geometry method is used to obtain the oil supply radius of oil wells. Drilling records are used to obtain the wellbore radius of the oil well. ; Basic reservoir parameters of five oil wells in the study area were obtained; see Table 1 for details. Table 1 Basic Reservoir Parameters .

[0032] Step 2: Obtain the bottomhole flowing pressure and fluid production index when each oil layer is producing independently; Five oil wells are in a syndicated production state, which is not suitable for verifying the accuracy of the fluid production index when producing independently. Therefore, in order to verify the accuracy of the fluid production index of each oil layer (C1, C2, and C3) when producing independently, the theoretical fluid production index values ​​of 15 adjacent oil wells in the study area when producing C1 (N6~N10), C2 (N11~N15), and C3 (N16~N20) independently were calculated using formula (2) (Table 2). The actual fluid production index (FPI) of 15 oil wells in different oil layers was calculated, verifying the theoretical value calculated by the FPI model (e.g., ...). Figures 2-4 (), exhibiting good consistency; Table 2. Fluid Production Index of Each Well When Producing a Single Oil Layer .

[0033] Step 3: Calculate the pressure loss generated by the fluid flowing from the lower oil layer to the upper oil layer in the 5 oil wells using formula (3). The calculation results are detailed in Table 3. Table 3. Pressure loss generated by fluid flowing from the lower oil layer to the upper oil layer in each oil well. The flow pressure difference between the oil layers when each oil layer of the 5 oil wells is producing independently was calculated using formula (4), and the results are shown in Table 4. Table 4. Flow pressure difference between oil layers when each oil well and oil layer is producing independently. .

[0034] Step 4: Compare the bottom hole pressure difference between oil layer 2 and oil layer 1 when the reservoir is produced alone with the pressure loss of the fluid flowing in the wellbore to obtain the remaining starting pressure of the disturbed oil layer when the two oil layers are produced together. like At that time, there is no interlayer interference in oil layer 2, and the remaining starting pressure of oil layer 1 is calculated using formula (5); if At that time, there was no interlayer interference in oil layer 1, and the remaining starting pressure of oil layer 2 was calculated by formula (6); the calculation results are detailed in Table 5. Table 5. Remaining starting pressure of the disturbed layer when any two layers are produced simultaneously in each oil well. .

[0035] Step 5: Obtain the corrected fluid recovery index of the disturbed oil layer based on the remaining start-up pressure; when At that time, interlayer interference exists in oil layer 1, and there is an additional pressure drop in the fluid flow within oil layer 1. The corrected production index of oil layer 1 is calculated using formula (7); when At that time, there is interlayer interference in oil layer 2, and there is an additional pressure drop in the fluid flow in oil layer 2. The corrected production index of oil layer 2 is calculated by formula (8).

[0036] Step 6: Obtain the corrected production index of the disturbed oil layer during multi-layer synergistic production using formula (9); the calculation results are detailed in Table 6. Table 6. Corrected Liquid Production Index .

[0037] Results Verification: The production volume of each oil layer was obtained based on the production profile, and then... The production of each oil layer was converted into a production index, and the actual production index was compared with the production index calculated by the model. Figures 5-7 ( ), which has good consistency.

[0038] Step 7: Calculate the total fluid production index of the oil well using formula (10). The results are detailed in Table 7; Table 7 Total Fluid Production Index of Oil Wells .

[0039] From Tables 6 and 7, we can see that:

[0040] N1 oil well: Three oil layers are developed, with oil layer 2 unaffected by the other two oil layers, and a fluid production index of 9.31 m. 3 / d·MPa; Layer 3 was the most severely disturbed, with the fluid production index dropping from 7.25 m / d in single-layer production. 3 / d·MPa decreased to 3.51 m after combined extraction. 3 / d·MPa, the loss reached 51.5%; the bottom-hole flowing pressure of oil layer 1 was between that of oil layer 2 and oil layer 3, and it was subject to the second most disturbances, with the fluid production index decreasing from 18.43 m in single-layer production. 3 / d·MPa decreased to 17.31m after combined mining. 3 / d·MPa, loss margin 6%; total fluid production index of the oil well is 30.13m 3 / d·MPa.

[0041] N2 oil well: Three oil-bearing layers are developed. Layer 2 is unaffected by the other two layers, and the fluid production index is 9.07 m. 3 / d·MPa; Layer 3 was the most severely disturbed, with the fluid production index dropping from 6.83 m³ / d to 100 m³ / d. 3 / d·MPa decreased to 3.24m after combined mining. 3 / d·MPa, the loss reached 52.5%; the bottom-hole flowing pressure of oil layer 1 was between that of oil layer 2 and oil layer 3, and it was subject to the second most disturbances, with the fluid production index decreasing from 17.21 m³ / d·MPa in single-layer production. 3 / d·MPa decreased to 15.92m after combined mining. 3 / d·MPa, loss margin 7.5%; total fluid production index of the oil well is 28.23m 3 / d·MPa.

[0042] N3 oil well: Three oil layers are developed, with oil layer 2 unaffected by the other two oil layers, and a fluid production index of 9.27 m. 3 / d·MPa; Layer 3 was the most severely disturbed, with the fluid production index dropping from 5.79 m in single-layer production. 3 / d·MPa decreased to 2.46m after combined mining. 3 / d·MPa, the loss reached 57.5%; the bottom-hole flowing pressure of oil layer 1 was between that of oil layer 2 and oil layer 3, and it was subject to the second most disturbances, with the fluid production index dropping from 17.78m in single-layer production. 3 / d·MPa decreased to 15.95m after combined mining. 3 / d·MPa, loss margin 10.3%; total fluid production index of the oil well is 27.68m 3 / d·MPa.

[0043] N4 oil well: Three oil layers are developed, with oil layer 2 unaffected by the other two layers, and a fluid production index of 9.76 m. 3 / d·MPa; Layer 3 was the most severely disturbed, with the fluid production index dropping from 7.24m in single-layer production. 3 / d·MPa decreased to 3.48m after combined mining. 3 / d·MPa, the loss reached 51.9%; the bottom-hole flowing pressure of oil layer 1 was between that of oil layer 2 and oil layer 3, and it was subject to the second most disturbances, with the fluid production index dropping from 16.86m³ / d·MPa in single-layer production. 3 / d·MPa decreased to 13.29m after combined mining. 3 / d·MPa, loss margin 21.2%; total fluid production index of the oil well 26.53m 3 / d·MPa.

[0044] N5 oil well: Three oil layers are developed, with oil layer 2 unaffected by the other two oil layers, and a fluid production index of 8.96 m. 3 / d·MPa; Layer 3 was the most severely disturbed, with the fluid production index dropping from 5.98m in single-layer production. 3 / d·MPa decreased to 2.64m after combined mining. 3 / d·MPa, the loss reached 55.9%; the bottom-hole flowing pressure of oil layer 1 was between that of oil layer 2 and oil layer 3, and it was subject to the second most disturbances, with the fluid production index decreasing from 17.21m in single-layer production. 3 / d·MPa decreased to 15.49m after combined mining. 3 / d·MPa, loss margin 9.9%; total fluid production index of the oil well is 27.10m 3 / d·MPa.

Claims

1. A method for calculating the fluid production capacity of a multi-layered syngas reservoir, characterized in that, The method is as follows: Obtain the bottomhole flowing pressure and fluid production index when each oil layer is producing independently; Calculate the pressure loss of fluid flowing in the wellbore and the flow pressure difference between two adjacent oil layers when they are producing independently; By comparing the bottom-hole pressure difference between oil layer 2 and oil layer 1 when the reservoir is produced alone with the pressure loss of fluid flowing in the wellbore, the remaining starting pressure of the disturbed oil layer when the two oil layers are produced together can be obtained. The corrected fluid production index of the disturbed oil layer is obtained based on the remaining start-up pressure. The corrected fluid production index of the disturbed oil layer in multi-layer combined production is obtained based on the two-layer combined production fluid production index model. The sum of the production indices of each oil layer is the total production index of the oil well.

2. The method for calculating the fluid production capacity of a multi-layered syngas reservoir according to claim 1, characterized in that, The specific solution process for the corrected fluid production index of the disturbed oil layer during multi-layer synergistic production is as follows: In the formula: The corrected production index for reservoir 1, m 3 / d·MPa; The effective permeability of oil layer 1, 10 -3 μm 3 ; The effective thickness of oil layer 1 is in meters (m). The viscosity of the fluid in layer 2 is mPa·s; The volume factor for oil layer 2; Provide a radius (m) for oil layer 2; Let be the radius of the wellbore, in meters (m). For fluid density, 10 3 kg / m 3 ; The formation pressure of oil layer 1 is MPa; The starting pressure gradient for oil layer 1 is MPa / m; Provide a radius of m for oil layer 1; The viscosity of the fluid in oil layer 1 is given in mPa·s. The volume factor for oil layer 1; For the effective permeability of oil layer 2, 10 -3 μm 3 ; The effective thickness of oil layer 2 is in meters. The formation pressure of oil layer 2 is MPa; oil layer Corrected liquid collection index, m 3 / d·MPa; For the effective permeability of oil layer j, 10 -3 μm 3 ; oil layer Effective thickness, m; oil layer Fluid viscosity, mPa·s; oil layer Volume index; oil layer Supply radius, m; oil layer Formation pressure, MPa; oil layer Initiate pressure gradient, MPa / m; For single-layer production oil layer Bottom hole flowing pressure, MPa; For single-layer production oil layer Bottom hole flowing pressure, MPa; For fluid from the oil layer Flow to the oil layer The total pressure drop during flow, MPa.

3. The method for calculating the fluid production capacity of a multi-layered syngas reservoir according to claim 2, characterized in that, The The bottom hole flowing pressure when each oil layer is producing independently is: （1） The fluid recovery index when each oil layer is producing fluids independently is: （2） In the formula: The bottomhole flowing pressure when the oil reservoir is producing independently; is the fluid viscosity, mPa·s; B is the volume coefficient, dimensionless. The supply radius is in meters (m). Let be the radius of the wellbore, in meters (m). Where is the diameter of the wellbore, in meters (m). For fluid density, 10 3 kg / m 3 ; For the effective permeability of the oil reservoir, 10 -3 μm 3 ; The effective thickness of the oil layer is in meters (m). G is the formation pressure, MPa; G is the starting pressure gradient, MPa / m. The fluid collection index, m 3 / d·MPa.

4. The method for calculating the fluid production capacity of a multi-layered syngas reservoir according to claim 3, characterized in that, The The pressure loss of fluid flowing inside the wellbore is: （3） When two oil layers are produced separately, the interlayer flow pressure difference is: （4） In the formula: The pressure loss caused by fluid flow within the wellbore, expressed in MPa. The acceleration due to gravity is m / s². 2 ; The vertical distance between oil layers, in meters (m). The pressure difference between the two oil layers during individual production, in MPa; The bottomhole flowing pressure (MPa) is the pressure when oil layer 2 is producing alone. The bottomhole flowing pressure (MPa) is the pressure when oil layer 1 is producing alone. For the effective permeability of oil layer 2, 10 -3 μm 3 ; The effective thickness of oil layer 2 is in meters. The formation pressure of oil layer 2 is MPa; The starting pressure gradient for oil layer 2 is MPa / m; Provide a radius (m) for oil layer 2; The viscosity of the fluid in layer 2 is mPa·s; The volume factor for oil layer 2; The effective permeability of oil layer 1, 10 -3 μm 3 ; The effective thickness of oil layer 1 is in meters (m). The formation pressure of oil layer 1 is MPa; The starting pressure gradient for oil layer 1 is MPa / m; Provide a radius of m for oil layer 1; The viscosity of the fluid in oil layer 1 is given in mPa·s. This is the volume factor for oil layer 1.

5. The method for calculating the fluid production capacity of a multi-layered syngas reservoir according to claim 4, characterized in that, The specific process for obtaining the remaining starting pressure of the disturbed oil layer during the combined production of the two oil layers is as follows: When two oil layers are produced together, if At that time, there is no interference between the oil layers, and the fluid production capacity remains unchanged; if At that time, there is inter-layer interference between oil layers, and the fluid production capacity changes. when At that time, there is no interlayer interference in oil layer 2, and the fluid flow within oil layer 2 has no additional pressure drop; there is interlayer interference in oil layer 1, and the fluid flow within oil layer 1 has an additional pressure drop. Its remaining starting pressure is: （5） when At that time, there is no interlayer interference in oil layer 1, and the fluid flow within oil layer 1 has no additional pressure drop; there is interlayer interference in oil layer 2, and the fluid flow within oil layer 2 has an additional pressure drop. Its remaining starting pressure is: （6） In the formula: The remaining starting pressure of oil layer 1 is MPa; The remaining starting pressure of oil layer 2 is MPa.

6. The method for calculating the fluid production capacity of a multi-layered syngas reservoir according to claim 5, characterized in that, The corrected fluid production index for the disturbed oil layer is: when At that time, interlayer interference existed in oil layer 1, and the fluid flow within oil layer 1 resulted in an additional pressure drop. The corrected production fluid index for oil layer 1 was: （7） when At that time, interlayer interference existed in oil layer 2, and the fluid flow within oil layer 2 resulted in an additional pressure drop. The corrected production index for oil layer 2 was: （8） In the formula: The corrected production index for reservoir 1, m 3 / d·MPa; The corrected production index for reservoir 2, m 3 / d·MPa.

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