Method for calculating variable skin factor in gas well screen pipe completion

Abstract

The application discloses a method for calculating a variable skin factor during screen pipe completion of a gas well, and comprises the following steps: obtaining screen pipe parameters, formation parameters, well parameters and fluid parameters; determining a slot turbulence coefficient, a formation turbulence coefficient and a Forchheimer coefficient; carrying out a solid-phase sulfur dissolution experiment in a gas under formation temperature; determining a total amount of solid-phase sulfur precipitation, a plugging width, a slot internal linear flow non-rate-dependent skin factor, a radial flow non-rate-dependent skin factor, a radial flow inertial resistance coefficient, a slot internal linear flow inertial resistance coefficient, a radial flow non-rate-dependent skin factor, a radial flow inertial resistance coefficient, a screen pipe external radial flow non-rate-dependent skin factor and a screen pipe external radial flow inertial resistance coefficient; and calculating a total screen pipe completion skin factor. The method realizes dynamic and accurate characterization of a skin factor of a high-sulfur gas well, and provides a reliable theoretical basis for gas well productivity evaluation, production system optimization and completion design.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for calculating time-varying skin factor of gas well screen completion, and belongs to the technical field of oil and gas exploitation. BACKGROUND

[0002] During the development of high-sulfur gas reservoirs, the dynamic change of skin factor of screen completion caused by sulfur deposition is a key factor affecting the productivity of gas wells. After the elemental sulfur precipitates with the change of formation pressure during production, it will form solid phase deposition in the screen slot, gradually blocking the flow channel. The traditional skin factor calculation method usually assumes that the skin factor is a constant value, only considers the static damage factor, and ignores the dynamic cumulative effect of sulfur deposition with the increase of production time, resulting in serious deviation of productivity prediction.

[0003] Therefore, it is necessary to establish a method for calculating time-varying skin factor of gas well screen completion to provide theoretical support for accurate prediction of the productivity of high-sulfur gas wells. SUMMARY

[0004] In view of the above problems, the present application mainly overcomes the shortcomings in the prior art and provides a method for calculating time-varying skin factor of gas well screen completion. The present application obtains dynamic data of sulfur deposition by carrying out solid phase sulfur dissolution experiment, establishes a quantitative relationship between sulfur deposition amount and pressure by using a polynomial function, and then accurately calculates the screen plugging thickness at different production periods and converts it into time-varying skin factor, solving the problem that the traditional static skin factor cannot reflect the dynamic change of sulfur deposition. This method realizes the dynamic and accurate characterization of the skin factor of high-sulfur gas wells, and provides a reliable theoretical basis for gas well productivity evaluation, production system optimization and completion design.

[0005] The technical solution provided by the present application to solve the above technical problems is: a method for calculating time-varying skin factor of gas well screen completion, comprising the following steps:

[0006] Obtain screen parameters, formation parameters, well parameters and fluid parameters;

[0007] Determine the slot turbulence coefficient, formation turbulence coefficient and Forchheimer coefficient based on the screen parameters;

[0008] Carry out a solid phase sulfur dissolution experiment in gas at the formation temperature, and determine the mathematical expression of the solubility of solid phase sulfur with pressure;

[0009] Determine the total amount of solid phase sulfur precipitation caused by pressure drop during production based on the mathematical expression of the solubility of solid phase sulfur with pressure;

[0010] Determine the plugging width caused by sulfur deposition in the slot based on the total amount of solid phase sulfur precipitation and screen parameters;

[0011] The non-rate-dependent skin factor of linear flow inside the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, and the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter.

[0012] The non-rate-dependent skin factor of linear flow inside the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, and the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter.

[0013] The non-rate-dependent skin factor of linear flow inside the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, and the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter.

[0014] The non-rate-dependent skin factor of linear flow inside the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter, and the non-rate-dependent skin factor of radial flow induced by the slot is determined based on the slot width caused by sulfur deposition and the screen parameter.

[0015] Further, the screen parameters include the number of slots distributed in the screen per unit length , the number of slots in the slot unit , the total number of slots distributed on the circumference , the slot width , the slot length , the slot thickness , the slot unit length , the permeability of the slot , the cross-slot spacing ; the formation parameters include the formation permeability , the original formation pressure , the formation temperature ; the well parameters include the well diameter , the length of the well ; the fluid parameters include the gas relative density , the gas viscosity .

[0016] Further, the calculation formula of the slot turbulence coefficient, the formation turbulence coefficient and the Forchheimer coefficient is respectively:

[0017]

[0018] In the formula: is the turbulence coefficient of the slot, dimensionless; is the permeability of the slot, mD;

[0019]

[0020] In the formula: is the turbulence coefficient of the formation, dimensionless; k is the formation permeability, mD;

[0021]

[0022] wherein: F is the Forchheimer coefficient, dimensionless; is the gas relative density, dimensionless; q is the current production, MMscf / D; is the gas viscosity, mPa-s; r w is the wellbore diameter, ft; L is the length of the well, ft.

[0023] Further, the technical scheme is that the solid-phase sulfur dissolution experiment in the gas at the formation temperature is carried out, and the mathematical expression of the solid-phase sulfur solubility with the pressure change is determined, and the mathematical expression of the solid-phase sulfur solubility with the pressure change comprises:

[0024] A pressure value sequence is determined, a formation gas sample is obtained by using a gas sampling tool, a solid-phase sulfur dissolution experiment in the gas at the formation temperature is carried out, and the solid-phase sulfur solubility data in the gas under the pressure sequence are determined;

[0025] The solid-phase sulfur dissolution experiment data under different pressures are fitted by using a polynomial function, and the mathematical expression of the solid-phase sulfur solubility with the pressure change is obtained.

[0026] Further, the technical scheme is that the total amount of the solid-phase sulfur precipitation is calculated according to the following formula:

[0027]

[0028] wherein: is the total mass of the solid-phase sulfur precipitation, g; is the current pressure, MPa; q is the current production, MMscf / D; is the original formation pressure, MPa; is a polynomial function of the pressure p .

[0029] Further, the technical scheme is that the calculation formula of the slotting internal plugging width caused by the sulfur deposition is as follows:

[0030]

[0031] wherein: is the slotting plugging width, ft; w s is the slot width, ft; is the density of the elemental sulfur, g / cm 3 ; is the slotting thickness, ft; is the length of the slot, ft; N s is the number of slots distributed in the unit length of the screen pipe, pieces / ft; is the number of slots in the slot unit, pieces; L is the length of the well, ft.

[0032] Further technical solutions are that the calculation formula of the slot internal linear flow non-rate-dependent skin factor, the multi-slot induced radial flow non-rate-dependent skin factor, and the multi-slot induced radial flow inertial resistance factor are respectively:

[0033]

[0034] In the formula, is the slot internal linear flow non-rate-dependent skin factor, dimensionless; is the length of the slot unit, ft; is the width of the slot after plugging, ft; is the length of the slot, ft; m s is the total number of slots distributed on the circumference of the screen pipe, pieces; is the number of slots in the slot unit, pieces; is the permeability in the slot, mD; k is the formation permeability, mD;

[0035]

[0036] In the formula, is the multi-slot induced radial flow non-rate-dependent skin factor, dimensionless; is the cross-slot spacing, ft;

[0037]

[0038] In the formula, is the multi-slot induced radial flow inertial resistance factor, dimensionless; r w is the well diameter, ft.

[0039] Further technical solutions are that the calculation formula of the slot internal linear flow inertial resistance factor is:

[0040]

[0041] In the formula, is the slot internal linear flow inertial resistance factor, dimensionless.

[0042] A further technical solution is that the calculation formulas for the radial flow non-rate-dependent skin coefficient induced by the circumferential distribution of the slotted unit, the radial flow inertial drag coefficient induced by the circumferential distribution of the slotted unit, the radial flow non-rate-dependent skin coefficient outside the screen tube, and the radial flow inertial drag coefficient outside the screen tube are as follows:

[0043]

[0044] In the formula: It is the radial flow non-rate-dependent skin coefficient induced by the circumferential distribution of slotted elements, and is dimensionless;

[0045]

[0046] In the formula: It is the radial flow inertial drag coefficient induced by the circumferential distribution of the slotted elements, and is dimensionless;

[0047]

[0048] In the formula: It is the non-rate-dependent skin coefficient of radial flow outside the sieve tube, and is dimensionless;

[0049]

[0050] In the formula: It is the radial flow inertial resistance coefficient outside the screen tube, and is dimensionless.

[0051] A further technical solution is that the formula for calculating the total skin factor of the screen completion is:

[0052]

[0053] In the formula: It is the total skin coefficient of the sieve tubes, dimensionless; It is a non-rate-dependent skin coefficient for linear flow inside the slot, and is dimensionless; It is the radial flow non-rate-dependent skin coefficient induced by multi-slot synergy, and is dimensionless; It is the radial flow non-rate-dependent skin coefficient induced by the circumferential distribution of slotted elements, and is dimensionless; It is the non-rate-dependent skin coefficient of radial flow outside the sieve tube, and is dimensionless; It is the linear flow inertial drag coefficient inside the slot, and is dimensionless; It is the radial flow inertial drag coefficient induced by the multi-slot synergy, and is dimensionless; It is the radial flow inertial drag coefficient induced by the circumferential distribution of the slotted elements, and is dimensionless; It is the radial flow inertial resistance coefficient outside the screen tube, dimensionless; Fis the Forchheimer coefficient, dimensionless.

[0054] The present application has the following beneficial effects: the present application precisely establishes the dynamic relationship between the sulfur deposition amount and the plugging thickness by solid phase sulfur dissolution experiment combined with polynomial function fitting, realizes the dynamic calculation of the skin factor in different production periods, and significantly improves the accuracy of the productivity prediction of high-sulfur gas wells;

[0055] Compared with the traditional static skin factor model, the method fully considers the cumulative effect of sulfur deposition over time, is more in line with the actual production dynamics, can provide a scientific basis for well completion optimization, productivity evaluation and production system adjustment in the development of high-sulfur gas reservoirs, and has important engineering application value. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 The process diagram of the screen pipe sulfur deposition plugging. DETAILED DESCRIPTION

[0057] The technical solutions of the present application will be described below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0058] The gas well screen pipe completion time-varying skin factor calculation method provided by the present application comprises the following steps:

[0059] Step S1, obtaining screen pipe parameters, formation parameters, well parameters and fluid parameters;

[0060] The screen pipe parameters include the number of slots distributed in the unit length of the screen pipe , the number of slots in the slot unit , the total number of slots distributed on the circumference , the slot width , the slot length , the slot thickness , the slot unit length , the permeability in the slot , the cross-slot spacing ; the formation parameters include the formation permeability , the original formation pressure , the formation temperature ; the well parameters include the well diameter , the length of the well ; the fluid parameters include the gas relative density , the gas viscosity .

[0061] Step S2, determine the slot turbulence coefficient, formation turbulence coefficient and Forchheimer coefficient according to the screen parameter;

[0062] (1)

[0063] wherein: is the turbulence coefficient of the slot, dimensionless; is the permeability in the slot, mD;

[0064] (2)

[0065] wherein: is the turbulence coefficient of the formation, dimensionless; k is the permeability of the formation, mD;

[0066] (3)

[0067] wherein: F is the Forchheimer coefficient, dimensionless; is the relative density of the gas, dimensionless; q is the current production, MMscf / D; is the viscosity of the gas, mPa·s; r w is the well diameter, ft; L is the length of the well, ft.

[0068] Step S3, prepare a pressure value sequence, use the gas sampling tool to obtain the formation gas sample, carry out the solid-phase sulfur dissolution experiment in the gas at the formation temperature, determine the solubility data of the solid-phase sulfur in the gas under the pressure sequence; and fit the solid-phase sulfur dissolution experiment data under different pressures by a polynomial function, to obtain a mathematical expression of the solubility of the solid-phase sulfur changing with the pressure;

[0069] (4)

[0070] wherein: C is the solubility of the solid-phase sulfur, g / m 3 ; is the pressure, MPa; is a polynomial function about the pressure ;

[0071] Step S4, determine the total amount of the solid-phase sulfur precipitation caused by the pressure drop in the production process based on the mathematical expression of the solubility of the solid-phase sulfur changing with the pressure;

[0072] (5)

[0073] wherein: is the total mass of solid-phase sulfur precipitation, g; is the current pressure, MPa; q is the current production, MMscf / D; is the original formation pressure, MPa;

[0074] Step S5, as shown in Figure 1 , the width of the slit caused by sulfur deposition is determined according to the total amount of solid-phase sulfur precipitation and the screen pipe parameters;

[0075] (6)

[0076] In the formula, is the width of the slit after the slit is blocked, ft; w s is the slit width, ft; is the density of elemental sulfur, g / cm 3 ; is the slit thickness, ft; is the slit length, ft; N s is the number of slits distributed in the unit length of the screen pipe, pieces / ft; is the number of slits in the slit unit, pieces; L is the length of the well, ft;

[0077] Step S6, the internal linear flow non-rate-dependent skin factor of the slit, the radial flow non-rate-dependent skin factor induced by the synergy of multiple slits, and the radial flow inertial resistance factor induced by the synergy of multiple slits are determined according to the width of the slit caused by sulfur deposition in the slit and the screen pipe parameters;

[0078] (7)

[0079] In the formula, is the internal linear flow non-rate-dependent skin factor of the slit, dimensionless; is the slit unit length, ft; is the slit length, ft;

[0080] (8)

[0081] In the formula, is the radial flow non-rate-dependent skin factor induced by the synergy of multiple slits, dimensionless; is the cross-slit spacing, ft;

[0082] (9)

[0083] In the formula, is the radial flow inertial resistance factor induced by the synergy of multiple slits, dimensionless; rw is the hole diameter, ft;

[0084] Step S7, determine the slot internal linear flow inertial resistance coefficient according to the width of the slot internal blockage caused by sulfur deposition and the screen parameter;

[0085] (10)

[0086] wherein: is the slot internal linear flow inertial resistance coefficient, dimensionless;

[0087] Step S8, determine the slot unit circumferential distribution induced radial flow non-rate dependent skin coefficient, the slot unit circumferential distribution induced radial flow inertial resistance coefficient, the screen external radial flow non-rate dependent skin coefficient and the screen external radial flow inertial resistance coefficient according to the screen parameter;

[0088] (11)

[0089] wherein: is the slot unit circumferential distribution induced radial flow non-rate dependent skin coefficient, dimensionless;

[0090] (12)

[0091] wherein: is the slot unit circumferential distribution induced radial flow inertial resistance coefficient, dimensionless;

[0092] (13)

[0093] wherein: is the screen external radial flow non-rate dependent skin coefficient, dimensionless;

[0094] (14)

[0095] wherein: is the screen external radial flow inertial resistance coefficient, dimensionless;

[0096] Step S9, calculate the total skin coefficient of the screen completion according to the Forchheimer coefficient ;

[0097] (15)

[0098] wherein: is the total skin coefficient of the screen, dimensionless.

[0099] Embodiment

[0100] The application provides a variable skin factor calculation method for gas well screen completion, and comprises the following steps:

[0101] Step S1, obtaining the number of slots distributed in the target gas well screen unit length is 60 / ft, the number of slots in the slot unit is 1, the total number of slots distributed on the circumference is 12, the slot width is 0.002 ft, the slot length is 0.2 ft, the slot thickness is 0.01 ft, the slot unit length is 0.24 ft, the permeability in the slot is 50 mD, the slot spacing is 0.3 ft, the formation permeability is 100 mD, the original formation pressure is 66.5 MPa, the formation temperature is 373 K, the well diameter is 0.3 ft, the length of the well is 2000 ft, the gas relative density is 0.753, the gas viscosity is 0.034 mPa·s, the density of elemental sulfur is 2.36 g / m 3 , the gas well production is 3.5 MMscf / D;

[0102] Step S2, the slot turbulence coefficient is calculated according to formulas (1)-(3) is 5.51*10 6 , the formation turbulence coefficient is 3.88*10 6 , the Forchheimer coefficient is 1.17*10 -4 ;

[0103] Step S3, a pressure sequence is proposed as , and the solubility corresponding to each pressure in the pressure sequence is 0.779, 1.543, 2.655, 3.947, 5.427, 6.413 g / m 3 , and the mathematical expression of the solid-phase sulfur solubility changing with pressure is ;

[0104] Step S4, the total amount of solid-phase sulfur precipitation caused by pressure drop during production is calculated according to formula (5) is 1481.67 g;

[0105] Step S5, the width of the slot after being blocked by sulfur deposition is calculated according to formula (6) is 1.85x10 -3 ft;

[0106] Step S6, the effective flow area of the slot is reduced due to sulfur deposition, and the non-rate-dependent skin factor of linear flow in the slot is calculated according to formula (7) is 2.27;

[0107] Step S7, the equivalent resistance of radial flow passage is increased due to flow interference between multiple slots, and the non-rate-dependent skin factor of radial flow induced by multiple slots is calculated according to formula (8) and (9) is 0.37, the inertial resistance coefficient of radial flow induced by multiple slots is 2.83;

[0108] Step S8, the influence of sulfur deposition at high speed flow is considered, and the inertial resistance coefficient of linear flow in the slot is calculated according to formula (10) is 54.85;

[0109] Step S9, the local flow resistance difference caused by uneven circumferential distribution of the slot is considered, and the non-rate-dependent skin factor of radial flow induced by circumferential distribution of the slot unit is calculated according to formula (11) and (12) is 0.045, the inertial resistance coefficient of radial flow induced by circumferential distribution of the slot unit is 0.0007,

[0110] Step S10, the radial flow far away from the screen pipe is considered, and the non-rate-dependent skin factor of radial flow outside the screen pipe is calculated according to formula (13) and (14) is -0.75, the inertial resistance coefficient of radial flow outside the screen pipe is 0.61;

[0111] Step S11, the flow area reduction caused by sulfur deposition and the multi-scale flow interference are considered, and the total skin factor of the screen pipe completion is calculated according to formula (15) is 1.94.

[0112] The above description does not limit the present application in any form, although the present application has been disclosed by the above examples, however, it is not intended to limit the present application, any skilled person in the art, without departing from the technical solution of the present application, can make some changes or modifications to the above disclosed technical content as equivalent examples, as long as it does not deviate from the technical solution of the present application, according to the technical essence of the present application, any simple modification, equivalent change and modification of the above examples, all belong to the scope of the technical solution of the present application.

Claims

1. A method for calculating variable skin factor in gas well screen completion, characterized in that, The method comprises the following steps: obtaining screen pipe parameters, formation parameters, well parameters and fluid parameters; determining a slit groove turbulence coefficient, a formation turbulence coefficient and a Forchheimer coefficient based on the screen pipe parameters; carrying out a solid-phase sulfur dissolution experiment in a gas at a formation temperature, and determining a mathematical expression of the solubility of the solid-phase sulfur varying with pressure; specifically comprising: preparing a pressure value sequence, obtaining a formation gas sample using a gas sampling tool, carrying out a solid-phase sulfur dissolution experiment in a gas at a formation temperature, and determining the solubility of the solid-phase sulfur in the gas at the pressure sequence; fitting the solid-phase sulfur dissolution experiment data at different pressures by a polynomial function to obtain the mathematical expression of the solubility of the solid-phase sulfur varying with pressure; determining the total amount of solid-phase sulfur precipitation caused by pressure drop during production based on the mathematical expression of the solubility of the solid-phase sulfur varying with pressure; determining the plugging width caused by sulfur deposition in the slit based on the total amount of solid-phase sulfur precipitation and the screen pipe parameters; determining a linear flow non-rate-dependent skin factor inside the slit, a radial flow non-rate-dependent skin factor induced by multiple slits and a radial flow inertial resistance factor induced by multiple slits based on the plugging width caused by sulfur deposition in the slit and the screen pipe parameters; determining a linear flow inertial resistance factor inside the slit based on the plugging width caused by sulfur deposition in the slit and the screen pipe parameters; determining a radial flow non-rate-dependent skin factor induced by circumferential distribution of the slit unit, a radial flow inertial resistance factor induced by circumferential distribution of the slit unit, a radial flow non-rate-dependent skin factor outside the screen pipe and a radial flow inertial resistance factor outside the screen pipe based on the screen pipe parameters; calculating a total skin factor of the screen pipe completion.

2. The method of claim 1, wherein, The screen parameters include the number of slots distributed per unit length of the screen , the number of slots per slot unit , the total number of slots distributed around the circumference , the slot width , the slot length , the slot thickness , the slot unit length , the permeability within the slot , the slot spacing ; the formation parameters include the formation permeability , the initial formation pressure , the formation temperature ; the well parameters include the wellbore diameter , the length of the well ; the fluid parameters include the gas relative density , the gas viscosity .

3. The method of claim 2, wherein, The calculation formulas of the slit groove turbulence coefficient, the formation turbulence coefficient and the Forchheimer coefficient are respectively: where: is the turbulence factor for the slotted fracture, dimensionless; is the permeability within the slotted fracture, mD; where: is the turbulent flow coefficient of the formation, dimensionless; k is the formation permeability, mD; where: F is the Forchheimer coefficient, dimensionless; is the gas relative density, dimensionless; q is the current production, MMscf / D; is the gas viscosity, mPa-s; r w is the wellbore diameter, ft; L is the length of the well, ft.

4. The method of claim 1, wherein, The calculation formula of the total amount of solid-phase sulfur precipitation is: where: is the total mass of solid phase sulfur precipitated, g; is the current pressure, MPa; q is the current production, MMscf / D; is the original formation pressure, MPa; is a polynomial function of pressure p .

5. The method of claim 4, wherein, The calculation formula of the plugging width caused by sulfur deposition in the slit is: In the formula: The width of the groove after it is sealed, in feet; w s It's the seam width, ft; This is the density of elemental sulfur, in g / cm³. 3 ; It is the groove thickness, ft; It is the grooving length, ft; N s It is the number of slots distributed per unit length of the screen tube, in units / ft; The number of seams within a seam unit; L It is the length of the well, in feet.

6. The method of claim 4, wherein, The calculation formulas of the linear flow non-rate-dependent skin factor inside the slit, the radial flow non-rate-dependent skin factor induced by multiple slits and the radial flow inertial resistance factor induced by multiple slits are respectively: where: is the slot internal linear flow non-rate dependent skin factor, dimensionless; is the slot unit length, ft; is the slot width after plugging, ft; is the slot length, ft; m s is the total number of slots distributed on the screen pipe circumference, number; is the number of slots within the slot unit, number / ft; is the slot permeability, mD; k is the formation permeability, mD; where: is the multi-slot coordinated induced radial flow non-rate dependent skin factor, dimensionless; is the cross-slot spacing, ft; where: is the multi-slot coordinated induced radial flow inertia resistance coefficient, dimensionless; r w is the hole diameter, ft.

7. The method of claim 3, wherein, The calculation formula of the linear flow inertial resistance factor inside the slit is: where: is the slot internal linear flow inertia resistance coefficient, dimensionless; is the slot width after clogging, ft.

8. The method of claim 3, wherein, The calculation formulas of the radial flow non-rate-dependent skin factor induced by circumferential distribution of the slit unit, the radial flow inertial resistance factor induced by circumferential distribution of the slit unit, the radial flow non-rate-dependent skin factor outside the screen pipe and the radial flow inertial resistance factor outside the screen pipe are respectively: where: is the radially flowing non-rate dependent skin coefficient induced by circumferential distribution of the slot units, dimensionless; wherein: is the coefficient of the radial flow inertia resistance induced by the circumferential distribution of the slot units, dimensionless; where: is the external radial flow non-rate dependent skin factor, dimensionless; where: is the external radial flow inertial resistance coefficient of the screen pipe, dimensionless.

9. The method of claim 1, wherein, The calculation formula of the total skin factor of the screen pipe completion is: wherein: is the total skin factor for the screen pipe, dimensionless; is the internal linear flow non-rate dependent skin factor for the slot, dimensionless; is the multi-slot induced radial flow non-rate dependent skin factor, dimensionless; is the slot unit circumferential distribution induced radial flow non-rate dependent skin factor, dimensionless; is the external radial flow non-rate dependent skin factor for the screen pipe, dimensionless; is the internal linear flow inertial resistance factor for the slot, dimensionless; is the multi-slot induced radial flow inertial resistance factor, dimensionless; is the slot unit circumferential distribution induced radial flow inertial resistance factor, dimensionless; is the external radial flow inertial resistance factor for the screen pipe, dimensionless; F is the Forchheimer factor, dimensionless.

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