CN102748007A - Well testing analytical method and device - Google Patents

Abstract

The invention provides a well test analysis method, comprising: measuring the basic parameters of the oil well and the fluids of each phase in the oil well; performing well test analysis of water flooding according to the basic parameters of the oil well and the fluids of each phase in the oil well , obtain the basic information of the reservoir during water flooding; select the single-phase oil in the multiphase flow during water flooding; use the basic information of the reservoir to perform pressure fitting to obtain the pseudo-viscosity of the single-phase oil; combine the The well test analysis of polymer flooding is carried out to obtain the basic information of the reservoir during polymer flooding, and the reservoir information during polymer flooding is monitored according to the basic information of the reservoir during polymer flooding. The well test analysis method provided by the invention can perform well test analysis based on polymer flooding, and monitor oil wells by analyzing the obtained basic information of oil reservoirs during polymer flooding. Correspondingly, the present invention also provides a well testing analysis device to realize the application in actual production.

Description

A well test analysis method and device

technical field

The application relates to the technical field of reservoir development, in particular to a well testing analysis method and device.

Background technique

During oil extraction, operators need to survey selected oil wells to determine whether the oil wells are located in the oil reservoir. At present, the method often used by developers is well test analysis, which is an important dynamic analysis method for understanding reservoirs, evaluating reservoirs and monitoring oil production dynamics.

The above-mentioned well test analysis can compare the measured results with the calculated results, and finally obtain the basic information of the reservoir, such as well storage constant, wellbore skin and permeability. Production personnel can further analyze the basic information of the reservoir to determine the pressure conductivity coefficient and rock characteristic parameters near the bottom of the well or between two wells; calculate the average formation pressure and the production capacity of the well; judge the characteristic parameters of the well, the wellbore Volume and wellbore pollution degree; Boundary types of oil layers discovered; Estimation of crude oil reserves in oil reservoirs to provide basis for oil reservoir development and maintenance.

However, the current well testing analysis is generally based on water flooding, and many oilfields in my country use polymer flooding to enhance oil recovery. Therefore, a well testing analysis based on polymer flooding is urgently needed.

Contents of the invention

The technical problem to be solved in this application is to provide a well testing analysis method, which can conduct well testing analysis based on polymer flooding, and obtain basic information of oil reservoirs during polymer flooding, so as to monitor the oil reservoirs.

In order to solve the above problems, the application discloses a well testing analysis method, comprising:

Measuring the basic parameters of the oil well and the fluids of each phase in said oil well;

According to the basic parameters of the oil well and the fluids of each phase in the oil well, the well test analysis of water flooding is carried out to obtain the basic information of the oil reservoir during water flooding;

Select single-phase oil in multi-phase flow during water flooding;

Using the basic information of the reservoir to perform pressure fitting to obtain the pseudo-viscosity of the single-phase oil;

Combined with the pseudo-viscosity, the well test analysis of polymer flooding is carried out to obtain the basic information of the reservoir during polymer flooding;

According to the basic information of the reservoir during polymer flooding, the reservoir information during polymer flooding is monitored.

Preferably, according to the basic parameters of the oil well and the fluids of each phase in the oil well, the well test analysis of water flooding is carried out, and the basic information of the reservoir during water flooding is obtained includes:

Measure the actual bottom hole pressure data during water flooding;

Select the geological model, wellbore type and reservoir boundary to obtain the preset basic information of the reservoir during water flooding;

According to the oil well and the basic parameters of each phase fluid in the oil well, the geological model, the wellbore type, the reservoir boundary and the preset basic information of the oil reservoir, the black oil model is used to calculate and obtain the bottom hole flow pressure during water flooding;

The actual pressure data during water flooding and the calculated bottom hole flowing pressure during water flooding are fitted to obtain the basic information of the reservoir during water flooding.

Preferably, the actual pressure data during water flooding is fitted with the calculated bottomhole flow pressure during water flooding, and the basic information of the reservoir during water flooding is obtained includes:

Obtain the actual pressure difference and pressure derivative during water flooding, and draw the log-logarithmic graph of the pressure difference and pressure derivative;

Obtaining the calculated pressure differential and pressure derivative during waterflooding, and plotting a log-log graph of said pressure differential and pressure derivative;

Fit the actual pressure difference and the log-log graph of the pressure derivative during water flooding with the calculated pressure difference and the log-log graph of the pressure derivative during water flooding. If the fitting accuracy is within the preset accuracy range, get The basic information of the reservoir at the time of water flooding is the required basic information of the reservoir; if the fitting accuracy is not within the predetermined accuracy range, modify the preset basic information of the reservoir at the time of water flooding, and carry out well test analysis of water flooding until the proposed The combined accuracy is within the preset accuracy range.

Preferably, performing pressure fitting using the basic information of the reservoir, and obtaining the pseudo-viscosity of the single-phase oil include:

According to the basic information of the reservoir during water flooding, the viscosity of the single-phase oil is changed, and well test analysis is performed to obtain the pseudo-viscosity of the single-phase fluid.

Preferably, the well test analysis of polymer flooding is carried out in combination with the pseudo-viscosity, and the basic information of the reservoir during polymer flooding is obtained including:

Select the oil-water two-phase model in the black oil model, in which the water phase is the polymer solution, the viscosity of the water phase is the viscosity of the polymer solution, the oil phase is single-phase oil, the oil phase viscosity is the pseudo viscosity, and the basic parameters of the water phase and the oil phase is the basic parameter of polymer solution and single-phase oil;

Measure the actual pressure data during polymer flooding;

Select the geological model, wellbore type and reservoir boundary to obtain the preset basic information of the reservoir during polymer flooding;

According to the basic parameters of the oil well and the basic parameters of the water phase and oil phase fluid, geological model, wellbore type, reservoir boundary and preset basic information of the reservoir during polymer flooding, the black oil model is used to calculate and obtain the polymer Bottom hole pressure during flooding;

The actual pressure data during polymer flooding and the calculated bottom hole flowing pressure during polymer flooding are fitted to obtain the basic information of the reservoir during polymer flooding.

Preferably, the actual pressure data during polymer flooding and the calculated bottom hole flow pressure during polymer flooding are fitted, and the basic information of the reservoir during polymer flooding includes:

Obtain the actual pressure difference and pressure derivative during polymer flooding, and draw the double-logarithmic graph of the pressure difference and pressure derivative;

Obtaining the calculated pressure difference and pressure derivative during polymer flooding, and plotting a log-log graph of said pressure difference and pressure derivative;

Fit the actual pressure difference and the log-log graph of the pressure derivative during polymer flooding with the calculated pressure difference and the log-log graph of the pressure derivative during polymer flooding, if the fitting accuracy is within the preset accuracy range , the basic reservoir information obtained during polymer flooding is the required basic reservoir information; if the fitting accuracy is not within the predetermined accuracy range, modify the preset basic information of the reservoir during polymer flooding, and carry out the polymer flooding test. Wells are analyzed until the fitting accuracy is within the preset accuracy range.

Preferably, the basic parameters of the oil well and each phase fluid in the oil well include: viscosity, volume coefficient, compressibility coefficient, fluid density, formation thickness, porosity and formation absolute permeability of the well and each phase fluid.

Preferably, the basic information of the reservoir includes: well storage constant, wellbore skin, permeability, initial pressure and original formation pressure.

The application also discloses a well testing analysis device, comprising:

The basic parameter measuring unit is used for measuring the basic parameters of the oil well and the fluids of each phase in the oil well;

The well test analysis unit of water flooding is used to perform well test analysis of water flooding according to the basic parameters of the oil well and the fluids of each phase in the oil well, and obtain the basic information of the oil reservoir during water flooding;

Pseudo-single-phase flow acquisition unit, used to select single-phase oil in multi-phase fluid during water flooding;

A pseudo-viscosity acquisition unit, configured to use the basic information of the reservoir to perform pressure fitting to obtain the pseudo-viscosity of the single-phase oil;

The well test analysis unit of polymer flooding is used to perform the well test analysis of polymer flooding in combination with the pseudo-viscosity to obtain the basic information of the reservoir during polymer flooding;

The monitoring unit is used to monitor the oil well according to the basic information of the oil reservoir during the polymer flooding.

Preferably, the well test analysis unit for water flooding includes:

The first measuring unit is used for measuring actual pressure data during water flooding;

The first selection unit is used to select the geological model, wellbore type and reservoir boundary during water flooding, and obtain the preset basic information of the reservoir during water flooding;

The first calculation unit is used to calculate and obtain the well during water flooding by using the black oil model according to the basic parameters of the oil well and the various phase fluids in the oil well, the geological model, the wellbore type, the reservoir boundary and the preset basic information of the reservoir underflow pressure;

The first pressure fitting unit fits the actual pressure data during water flooding and the calculated bottomhole flowing pressure during water flooding to obtain basic information of the reservoir during water flooding.

Preferably, the first pressure fitting unit includes:

The first logarithmic diagram drawing unit is used to respectively obtain the actual and calculated pressure difference and pressure derivative during water flooding, and draw a double-logarithmic diagram of the pressure difference and pressure derivative;

The first logarithmic map fitting unit is used to fit the actual pressure difference and the double logarithmic map of the pressure derivative during water flooding to the calculated pressure difference and the double logarithmic map of the pressure derivative during water flooding;

The first fitting accuracy judging unit is used to judge whether the fitting accuracy is within the preset accuracy range. If the fitting accuracy is within the preset accuracy range, the obtained basic reservoir information during water flooding is the required basic reservoir information. information; if the fitting accuracy is not within the preset accuracy range, modify the preset basic information of the reservoir during water flooding, and perform water flooding well test analysis until the fitting accuracy is within the preset accuracy range.

Preferably, the polymer flooding well test analysis unit includes:

The second measurement unit is used to measure the actual pressure data at the bottom of the well during polymer flooding;

The second selection unit is used to select the geological model, wellbore type and reservoir boundary during polymer flooding, and obtain the preset basic information of the reservoir during polymer flooding;

The second calculation unit is used to use the black oil model to calculate and obtain the polymer flooding time according to the basic parameters of the oil well and the oil phase and water phase fluid, geological model, wellbore type, reservoir boundary and preset basic information of the reservoir bottom hole pressure;

The second pressure fitting unit is used to fit the actual pressure data during polymer flooding and the calculated bottom hole flow pressure during polymer flooding to obtain basic information of the reservoir during polymer flooding.

Preferably, the second pressure fitting unit includes:

The second logarithmic diagram drawing unit is used to respectively obtain the actual and calculated pressure difference and pressure derivative during polymer flooding, and draw a double-logarithmic diagram of the pressure difference and pressure derivative;

The second logarithmic map fitting unit is used to fit the actual pressure difference and the double logarithmic map of the pressure derivative during polymer flooding to the calculated double logarithmic map of the pressure difference and pressure derivative during polymer flooding ;

The second fitting accuracy judging unit is used to judge whether the fitting accuracy is within the preset accuracy range, if the fitting accuracy is within the preset accuracy range, the acquired basic information of the reservoir during polymer flooding is the required reservoir Basic information; if the fitting accuracy is not within the preset accuracy range, modify the preset basic information of the reservoir during polymer flooding, and perform polymer flooding well test analysis until the fitting accuracy is within the preset accuracy range.

Preferably, it also includes:

Oil well production measurement unit, used to measure the production of oil wells in different time periods during water flooding and polymer flooding;

Reservoir flow section division unit is used to divide the reservoir into multiple flow sections according to the production of the oil wells in different time periods during the well test analysis of water flooding and polymer flooding. The well test analysis of water flooding and the well test analysis of polymer flooding are carried out in sequence.

Preferably, the basic parameters of the oil well and each phase fluid in the oil well include: viscosity, volume coefficient, compressibility coefficient, fluid density, formation thickness, porosity and formation absolute permeability of the well and each phase fluid.

Preferably, the basic information of the reservoir includes: well storage constant, wellbore skin, permeability, initial pressure and original formation pressure.

Compared with the prior art, the present application includes the following advantages:

In this application, the oil well and the basic parameters of each phase fluid in the oil well are measured first, and then the basic information of the reservoir during water flooding and the pseudo-viscosity of the single-phase fluid are obtained, and then combined with the pseudo-viscosity to conduct well test analysis of polymer flooding The basic information of the oil reservoir during polymer flooding is obtained, and the oil well is monitored according to the basic information of the oil reservoir during polymer flooding. Therefore, the present application can conduct well test analysis based on polymer flooding, and can monitor the oil well according to the basic information of the oil reservoir during polymer flooding.

Of course, implementing any product of the present application does not necessarily need to achieve all the above-mentioned advantages at the same time.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

Fig. 1 is a flow chart of a well testing analysis method provided by the application;

Fig. 2 is a subflow chart of a kind of well test analysis method provided by the present application;

Fig. 3 is another subflow chart of a kind of well test analysis method provided by the present application;

Fig. 4 is another subflow chart of a kind of well test analysis method provided by the present application;

Fig. 5 is another subflow chart of a kind of well test analysis method provided by the present application;

Fig. 6 is an example diagram of oilfield development provided by the present application;

Fig. 7 is the distribution diagram of formation permeability during polymer flooding provided by the present application;

Fig. 8 is the pressure fitting diagram during the well test analysis of water flooding provided by the present application;

Fig. 9 is the pressure fitting diagram during the well test analysis of the polymer flooding provided by the present application;

Fig. 10 is a schematic structural view of a well testing analysis device provided by the present application;

Fig. 11 is a schematic structural view of the water drive well test analysis unit in the well test analysis device provided by the present application;

Fig. 12 is a schematic structural diagram of the pressure fitting unit in the water drive well test analysis unit of the well test analysis device provided by the present application;

Fig. 13 is a structural schematic diagram of the polymer flooding well test analysis unit in the well test analysis device provided by the present application;

Fig. 14 is a schematic structural diagram of the pressure fitting unit in the polymer flooding well test analysis unit of the well test analysis device provided by the present application;

Fig. 15 is another structural schematic diagram of a well testing analysis device provided by the present application.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

Referring to Fig. 1, it shows the flow chart of a kind of well test analysis method of the present application, can comprise the following steps:

Step 11: Measure the basic parameters of the oil well and the fluids of each phase in the oil well.

In this embodiment, the oil well and the basic parameters of each phase fluid in the oil well can be measured through oilfield experiments. Wherein, each phase fluid may include water phase, oil phase and gas phase. The basic parameters may include the viscosity, volume coefficient, compressibility coefficient, fluid density, formation thickness, porosity and formation absolute permeability (hereinafter referred to as "permeability") of the well and each phase fluid.

It should be pointed out here that before the well test analysis of water flooding or polymer flooding, it is necessary to divide the flow section of the reservoir, which is conducive to improving the accuracy of well test analysis.

Wherein, the division of the flow section may include: measuring the production of the oil well in different time periods during water flooding, dividing the reservoir into multiple flow sections according to the production of the oil well in different time periods, Well test analysis of water flooding can be carried out sequentially;

Measure the production of oil wells in different time periods during polymer flooding, divide the reservoir into multiple flow sections according to the production of the oil wells in different time periods, and perform polymer flooding in sequence on the divided multiple flow sections Well test analysis.

Step 12: According to the basic parameters of the oil well and the fluids of each phase in the oil well, conduct well test analysis of water flooding, and obtain basic information of the oil reservoir during water flooding.

In this embodiment, the well test analysis of water flooding can be performed using the black oil model, and the basic information of the reservoir during water flooding can be obtained according to the results of the well test analysis. The basic information of the reservoir includes: well storage constant, wellbore skin, permeability, initial pressure and original formation pressure.

The specific expression of the black oil model is as follows:

Oil composition:

$<span\; class="notranslate">\; \&dtri;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; K</span>}{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; ro</span>}}}{{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; \&dtri;</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&dtri;</span>\mathrm{<span\; class="notranslate">\; Z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; \&PartialD;</span>}{<span\; class="notranslate">\; \&PartialD;</span>\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; \&phi;</span>}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}{{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; osc</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Water component:

$<span\; class="notranslate">\; \&dtri;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; K</span>}{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; rw</span>}}}{{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; \&dtri;</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; \&dtri;</span>\mathrm{<span\; class="notranslate">\; Z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; \&PartialD;</span>}{<span\; class="notranslate">\; \&PartialD;</span>\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; \&phi;</span>}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}}{{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; wsc</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Gas composition:

$<span\; class="notranslate">\; \&dtri;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; K</span>}{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; ro</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}}{{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; \&dtri;</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&dtri;</span>\mathrm{<span\; class="notranslate">\; Z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; K</span>}{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; r\; g</span>}}}{{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; \&dtri;</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; \&dtri;</span>\mathrm{<span\; class="notranslate">\; Z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span>$

$<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; \&PartialD;</span>}{<span\; class="notranslate">\; \&PartialD;</span>\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}\mathrm{<span\; class="notranslate">\; \&phi;</span>}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}{{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&phi;</span>}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}{{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; osc</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; fgsc</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

in,

S _o +S _w +S _g =1 (4)

p _cow =p _o -p _w =f(S _w ,S _g ) (5)

p _cgo =p _g -p _o =f(S _w ,S _g ) (6)

In the formula, the oil component, water component and gas component can be oil phase, water phase and gas phase respectively, o, w, g are the subscripts of oil, water and gas phase; K is the absolute permeability of the formation; K _ro , K _rw , K _rg are relative permeability of oil phase, water phase and gas phase respectively; B is formation volume coefficient; μ is viscosity; γ is relative density; p is pressure; Z is vertical coordinate; R _s is ratio of dissolved oil and gas _; is the component yield or flow.

In formulas (1)-(3), K _ro , K _rw , K _rg , _pcow , and _pcgo are functions of saturation. in:

K _rw =K _rw (S _w )

K _rg =K _rg (S _g )

K _ro =K _ro (S _o )=K _ro (S _w ,S _g )

p _cow =f(S _w )

p _cgo =f(S _g )

K _rw , K _rg , _pcow , and _pcgo can all be obtained from the experimental data of oil-water and oil-gas two-phase flow, and K _ro needs to be calculated using formulas such as Stone.

B _o , B _w , B _g are the volume coefficients of the fluids of each phase; μ _o , μ _w , μ _g are the viscosities of the fluids of each phase; γ _o , γ _w , γ _g are the relative densities of the fluids of each phase. In the three-phase state, that is, the oil phase saturation state, the relative density, volume coefficient, and viscosity of each phase fluid are all functions of the pressure P, such as:

B _o =f(p)

R _s =f(p)

μ _o =f(p)

In the unsaturated state of the oil phase, when there are only two phases of oil and water in the reservoir, the relative density, volume coefficient, and viscosity of each phase fluid are functions of the bubble point pressure p _b and the pressure p, such as:

B _o =f(p,p _b )

ρ _o =f(p,p _b )

μ _o =f(p,p _b )

If the rock pore volume changes significantly with pressure, then:

φ=φ ^ref [1+C _r (pp ^ref )]

where C _r is the rock compressibility coefficient; φ is the porosity; φ ^ref is the porosity at the reference pressure pre ^ref .

When using the black oil model for water flooding well test analysis, it is necessary to select the multiphase fluid model in the black oil model according to the actual situation of the reservoir. For example, the oil-water two-phase model and the oil-gas-water three-phase model can be selected. In this embodiment Choose the oil-water-gas three-phase model.

In this embodiment, the above-mentioned substituting the basic parameters of the oil well and the fluids of each phase in the oil well into the black oil model, and the specific process of obtaining the basic information of the reservoir during water flooding, please refer to Figure 2, and may include the following steps:

Step 201: Measure the actual bottomhole pressure data during water flooding.

Step 202: Select the geological model, wellbore type and reservoir boundary to obtain preset basic information of the reservoir during water flooding.

In the well test analysis of water drive, it is necessary to select the geological model, wellbore type and reservoir boundary suitable for the test analysis of water drive, and obtain the preset parameter values of the basic information of the reservoir in water drive according to the reservoir production experience .

Among them, in the well test analysis, it is necessary to select the corresponding geological model, wellbore type and reservoir boundary for different reservoirs according to the understanding of the reservoir and different construction schemes in the process of reservoir exploitation.

Step 203: According to the oil well and the basic parameters of each phase fluid in the oil well, the geological model, the wellbore type, the reservoir boundary and the preset basic information of the reservoir, use the black oil model to calculate and obtain the bottom hole flow pressure during water flooding.

Step 204: Fitting the actual pressure data during water flooding and the calculated bottomhole flowing pressure during water flooding to obtain basic information of the reservoir during water flooding.

In this embodiment, the process of pressure fitting is shown in Figure 3, and may include the following steps:

Step 301: Obtain the actual pressure difference and pressure derivative during water flooding, and draw a logarithmic graph of the pressure difference and pressure derivative.

Step 302: Obtain the calculated pressure difference and pressure derivative during water flooding, and draw a logarithmic graph of the pressure difference and pressure derivative.

Among them, the formulas for calculating the pressure difference and pressure derivative are as follows,

Let (T ₀ , P ₀ ) (T ₁ , P ₁ ),…, (T _n , P _n ) be the pressure at different times, then the pressure difference is: Δp ₁ =P ₁ -P ₀ ,…,Δp _n =P _n -P ₀

The pressure derivative is: dp ₁ = (P ₁ -P ₀ )/(T ₁ -T ₀ )*T ₁ ,…,dp _n = (P _n -P _n-1 )/(T _n -T _n-1 ) *T _n-1

Among them, the drawing of the double-log graph is based on the coordinate size on the pressure drop chart.

Step 303: Fitting the actual pressure difference and the log-log graph of the pressure derivative during the water flooding with the calculated pressure difference and the log-log graph of the pressure derivative during the water flooding.

Step 304: Determine whether the fitting accuracy is within the preset accuracy range, if yes, go to step 305; if not, go to step 306.

Among them, the preset accuracy range can be set to different accuracy ranges according to the conditions of the reservoir in the application scenario, and there is no limitation on this.

Step 305: Obtaining the basic information of the reservoir during water flooding is the required basic information of the reservoir.

Step 306: modify the preset basic information of the reservoir, and perform water flooding well test analysis until the fitting accuracy is within the preset accuracy range.

Among them, when the accuracy is not satisfied, by observing the difference between the measured curve and the calculated curve, according to the flow law of the seepage equation and the influence of different preset parameters on the shape of the calculated curve, select the parameters that need to be adjusted for modification. For example, the "opening" of the calculated curve and the measured curve is different, and the pressure fitting can be performed by adjusting the wellbore pollution parameters.

To modify the preset basic information of the reservoir, the specific parameter values in the basic information of the reservoir can be modified, and the modified basic information of the reservoir can be used as the preset basic information of the reservoir. The basic parameters, geological model, wellbore type, reservoir boundary and preset basic information of the reservoir are used for well test analysis of water flooding. For the specific process of well test analysis of water drive, please refer to Figure 2 for fitting.

Step 13: Select the single-phase oil in the multi-phase fluid during water flooding.

Wherein, after selecting the single-phase oil in the multi-phase fluid at the bottom of the well, the single-phase oil is a pseudo-single phase. The single-phase oil model in the black oil model is selected for well test analysis. The calculation model is as follows:

$<span\; class="notranslate">\; \&dtri;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; K</span>}}{{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; \&dtri;</span>{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&dtri;</span>\mathrm{<span\; class="notranslate">\; Z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; \&PartialD;</span>}{<span\; class="notranslate">\; \&PartialD;</span>\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; \&phi;</span>}}{{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; osc</span>}}$

The volume coefficient and compressibility coefficient calculation formula of pseudo-single phase are as follows:

Pseudo-single-phase volume coefficient = oil phase saturation * oil phase volume coefficient + water phase saturation * water phase volume coefficient; pseudo-single-phase compression coefficient = oil phase saturation * oil phase compression coefficient + water phase saturation * water phase compression coefficient.

The parameter values of the pseudo-single phase can be obtained by reservoir experiments and calculation methods.

Among them, in the well test analysis, the production system of the well should be formulated according to the selected multi-phase fluid at the bottom of the well. The production system is defined as constant water production, and the production system of the well when oil-water two-phase is selected is defined as constant oil-water production.

Step 14: Using the basic information of the reservoir to perform pressure fitting to obtain the pseudo-viscosity of the single-phase oil.

Specifically: obtaining the calculated pressure difference and pressure derivative under the single-phase oil model, and drawing a double-logarithmic graph of the pressure difference and pressure derivative. The formulas for calculating the pressure difference and pressure derivative are:

Let (T ₀ , P ₀ ) (T ₁ , P ₁ ),…, (T _n , P _n ) be the pressure at different times, then the pressure difference is: Δp ₁ =P ₁ -P ₀ ,…,Δp _n =P _n -P ₀

The pressure derivative is: dp ₁ = (P ₁ -P ₀ )/(T ₁ -T ₀ )*T ₁ ,…,dp _n = (P _n -P _n-1 )/(T _n -T _n-1 ) *T _n-1

The log-log plots of the calculated pressure differences and pressure derivatives under the single-phase oil model were fitted to those for the water flood. Determine whether the fitting accuracy is within the preset accuracy range. If so, the viscosity of the single-phase oil is the required pseudo-viscosity. If it is not within the preset accuracy range, change the viscosity of the single-phase oil and perform calculations under the single-phase oil model. The log-log graph of the pressure difference and pressure derivative is fitted with the calculated pressure difference and log-log graph of the pressure derivative during water flooding until the fitting accuracy is within the preset range.

Among them, the preset accuracy range can be set to different accuracy ranges according to the conditions of the reservoir in the application scenario, and there is no limitation on this.

Step 15: Combined with the pseudo-viscosity, the well test analysis of polymer flooding is carried out to obtain the basic information of the reservoir during polymer flooding.

The well test analysis of polymer flooding can be carried out using the black oil model. The specific process of well test analysis of polymer flooding is shown in Figure 4, which can include the following steps:

Step 401: Select the oil-water two-phase model in the black oil model as a calculation model for well test analysis of polymer flooding.

Among them, the oil phase is a single-phase oil, the viscosity of the oil phase is the pseudoviscosity, the water phase is the polymer solution, the viscosity of the water phase is the viscosity of the polymer solution, and the basic parameters of the oil phase and the water phase are the single-phase oil and the polymer solution respectively basic parameters.

Among them, the basic parameters of oil phase and water phase can be obtained through reservoir experiments and calculation methods.

Step 402: Measure actual pressure data during polymer flooding.

Step 403: Select the geological model, wellbore type and reservoir boundary to obtain the preset basic information of the reservoir during polymer flooding.

In the well test analysis of polymer flooding, it is necessary to select the geological model, wellbore type and reservoir boundary suitable for the well test analysis of polymer flooding, and obtain the preset of the basic information of the polymer flooding reservoir according to the oil field production experience parameter value.

Step 404: According to the measured basic parameters of the oil well and the basic parameters of oil phase and water phase fluid, geological model, wellbore type, reservoir boundary and preset basic information of the reservoir during polymer flooding, use the black oil model to calculate and obtain Bottomhole flowing pressure during polymer flooding.

Step 405: Fitting the actual pressure data during polymer flooding and the calculated bottom hole flowing pressure during polymer flooding to obtain basic information of the reservoir during polymer flooding.

In this embodiment, the process of pressure fitting is shown in Figure 5, and may include the following steps:

Step 501: Obtain the actual pressure difference and pressure derivative during polymer flooding, and draw a logarithmic graph of the pressure difference and pressure derivative.

Step 502: Obtain the calculated pressure difference and pressure derivative during polymer flooding, and draw a logarithmic graph of the pressure difference and pressure derivative.

Among them, the drawing of the double-log graph is based on the coordinate size on the pressure drop chart.

Step 503: Fitting the actual pressure difference and the double-logarithmic diagram of the pressure derivative during the polymer flooding with the calculated pressure difference and the double-logarithmic diagram of the pressure derivative during the polymer flooding.

Step 504: Determine whether the fitting accuracy is within the preset accuracy range, if yes, go to step 505; if not, go to step 506.

Step 505: The acquired basic reservoir information during polymer flooding is the required basic reservoir information.

Step 506: Modify the preset basic information of the reservoir during polymer flooding, and perform well test analysis of polymer flooding until the fitting accuracy is within the preset accuracy range.

Among them, the modification of the preset basic information of the oil reservoir can specifically be carried out by modifying the specific parameter values in the basic information of the oil reservoir, using the modified basic information of the oil reservoir as the preset basic information of the oil reservoir, and again according to the oil well and the value in the oil well. The basic parameters of each phase fluid, geological model, wellbore type, reservoir boundary and preset basic information of the reservoir are used for well test analysis of polymer flooding. For the specific process of well test analysis of polymer flooding, please refer to Fig. 4 for fitting.

Step 16: Monitoring the oil well according to the basic information of the reservoir during polymer flooding.

Please refer to Figure 6, which shows an example of the application monitoring oil wells based on the basic information of the reservoir during polymer flooding. In a certain reservoir area, there is one production well in the middle and four injection wells around it. Water is injected into the injection well during water flooding, polymer solution is injected into the injection well during polymer flooding, and oil reservoirs are recovered in the production well.

When the well testing analysis method of the prior art is used for the well testing analysis of polymer flooding, the obtained basic information of the reservoir: the wellbore skin is -0.23, the well storage constant is 0.7 (m ³ /MPa), and the average formation permeability is 800mD. Among them, the oil phase viscosity is 8.9mPa.s, and the water phase viscosity is 0.6mPa.s.

The well test analysis method provided by this application was used for polymer flooding well test analysis. Among the obtained basic information of the reservoir: the wellbore skin is 5, the well storage constant is 0.8 (m ³ /MPa), and the formation permeability distribution is shown in Figure 7 shows that the viscosity of the polymer solution is 12mPa.s.

After selecting the single-phase oil in the multi-phase fluid, the pseudo-viscosity obtained by pressure fitting is 2.9 mPa.s.

Among them, the pressure fitting diagram of water flooding well test analysis is shown in Fig. 8, and the pressure fitting situation of polymer flooding is shown in Fig. 9.

The upper part of the graphs in Fig. 8 and Fig. 9 is the fitting graph of the measured pressure drop and its derivative and the calculated pressure drop and its derivative; the lower part of the graph is the fitting graph of the measured pressure and the calculated pressure.

Obviously, when the well test analysis method provided by this application is used for polymer flooding well test analysis, the formation permeability is obviously reduced, and the well skin changes from negative to positive, which is in line with the oilfield development dynamics. Among them, the oilfield dynamics are the characteristics shown in the oilfield development process. The larger the wellbore skin becomes, the more difficult the flow is. The permeability represents the penetration ability of the polymer solution in the formation. The polymer will cause pollution, so the more the polymer solution flows Difficult, the lower the permeability the better.

It can be seen that the wellbore skin obtained by using the existing well test analysis method for polymer flooding well test analysis is often a negative value with a large absolute number, which does not conform to the oilfield dynamics and is wrong.

Applying the above technical scheme, first measure the basic parameters of the oil well and each phase fluid in the oil well, secondly obtain the basic information of the reservoir during water flooding and the pseudo-viscosity of the single-phase fluid, and then conduct the well test analysis of polymer flooding in combination with the pseudo-viscosity The basic information of the oil reservoir during polymer flooding is obtained, and the oil well is monitored according to the basic information of the oil reservoir during polymer flooding. Therefore, the present application can conduct well test analysis based on polymer flooding, and can monitor the oil well according to the basic information of the oil reservoir during polymer flooding.

Corresponding to the above method, the present application also provides a well test analysis device to ensure the realization and application of the above method in practice. Please refer to Fig. 10, which shows a schematic structural diagram of a well test analysis device of the present application, which may include the following structural units: basic parameter measurement unit 101, water flooding well test analysis unit 102, pseudo-single-phase flow acquisition A unit 103 , a pseudo-viscosity acquisition unit 104 , a polymer flooding well test analysis unit 105 and a monitoring unit 106 . in,

The basic parameter measurement unit 101 is used to measure the basic parameters of the oil well and the fluids of each phase in the oil well.

The water flooding well test analysis unit 102 is used for performing water flooding well test analysis according to the basic parameters of the oil well and the fluids of each phase in the oil well, and obtaining the basic information of the oil reservoir during water flooding. Please refer to FIG. 11 for its specific structure. The well test analysis unit 102 of water flooding includes: a first measurement unit 201, a first selection unit 202, a first calculation unit 203 and a first pressure fitting unit 204, wherein,

The first measurement unit 201 is used to measure the actual bottom hole pressure data during water flooding.

The first selection unit 202 is used to select the geological model, wellbore type and reservoir boundary during water flooding, and obtain preset basic information of the reservoir during water flooding.

The first calculation unit 203 is used to calculate and obtain the water flooding time by using the black oil model according to the basic parameters of the oil well and the various phase fluids in the oil well, the geological model, the wellbore type, the reservoir boundary and the preset basic information of the oil reservoir. bottom hole pressure.

The first pressure fitting unit 204 is configured to fit the actual pressure data during water flooding and the calculated bottomhole flow pressure during water flooding to obtain basic information of the reservoir during water flooding. Referring to FIG. 12 for its specific structure, the first pressure fitting unit 204 includes: a first logarithmic diagram drawing unit 301 , a first logarithmic diagram fitting unit 302 and a first fitting accuracy judging unit 303 . in,

The first logarithmic diagram drawing unit 301 is used to respectively obtain the actual and calculated pressure difference and pressure derivative during water flooding, and draw a double-logarithmic diagram of the pressure difference and pressure derivative.

The first logarithmic diagram fitting unit 302 is configured to fit the actual pressure difference and the logarithmic diagram of the pressure derivative during water flooding with the calculated pressure difference and the loglogarithmic diagram of the pressure derivative during water flooding.

The first fitting accuracy judging unit 303 is used to judge whether the fitting accuracy is within the preset accuracy range, if the fitting accuracy is within the preset accuracy range, the acquired basic information of the reservoir during water flooding is the required reservoir Basic information; if the fitting accuracy is not within the preset accuracy range, modify the preset basic information of the reservoir during water flooding, and conduct water flooding well test analysis until the fitting accuracy is within the preset accuracy range.

The pseudo-single-phase flow acquisition unit 103 is used to select single-phase oil in the multi-phase fluid during water flooding. .

The pseudo-viscosity acquisition unit 104 is configured to use the basic information of the reservoir to perform pressure fitting to obtain the pseudo-viscosity of the single-phase oil.

The polymer flooding well test analysis unit 105 is used to perform polymer flooding well test analysis in combination with the pseudo-viscosity to obtain basic information of the reservoir during polymer flooding. Please refer to FIG. 13 for its specific structure. The well test analysis unit 105 of polymer flooding includes: a second measurement unit 401 , a second selection unit 402 , a second calculation unit 403 and a second pressure fitting unit 404 . in,

The second measurement unit 401 is used to measure the actual pressure data at the bottom of the well during polymer flooding.

The second selection unit 402 is used to select the geological model, wellbore type and reservoir boundary during polymer flooding, select the oil-water two-phase model in the black oil model, and obtain preset basic information of the reservoir during polymer flooding.

The second calculation unit 403 is used to calculate and obtain polymer flooding by using the black oil model according to the basic parameters of the oil well and the oil phase and water phase fluid, geological model, wellbore type, reservoir boundary and preset basic information of the reservoir. Bottomhole flow pressure at .

The second pressure fitting unit 404 is used to fit the actual pressure data during polymer flooding and the calculated bottomhole flow pressure during polymer flooding to obtain basic information of the reservoir during polymer flooding. Please refer to FIG. 14 for its specific structure. The second pressure fitting unit 404 includes: a second logarithmic graph drawing unit 501, a second logarithmic graph fitting unit 502 and a second fitting accuracy judgment unit 503, wherein,

The second logarithmic diagram drawing unit 501 is used to respectively obtain the actual and calculated pressure difference and pressure derivative during polymer flooding, and draw a logarithmic diagram of the pressure difference and pressure derivative.

The second logarithmic diagram fitting unit 502 is used to simulate the double logarithmic diagram of the actual pressure difference and pressure derivative during polymer flooding and the calculated pressure difference and pressure derivative during polymer flooding combine.

The second fitting accuracy judging unit 503 is used to judge whether the fitting accuracy is within the preset accuracy range, if the fitting accuracy is within the preset accuracy range, the obtained basic reservoir information during polymer flooding is the required reservoir Basic information; if the fitting accuracy is not within the preset accuracy range, modify the preset basic information of the reservoir during polymer flooding, and perform polymer flooding well test analysis until the fitting accuracy is within the preset accuracy range.

The monitoring unit 106 is configured to monitor the oil well according to the basic information of the reservoir during polymer flooding.

In this embodiment, before the well test analysis of water flooding or polymer flooding, it is necessary to divide the flow section of the reservoir, which is beneficial to improve the accuracy of the well test analysis. Please refer to Figure 15, which shows a Another schematic diagram of the structure of the well testing analysis device, based on FIG. in,

The oil well production measurement unit 107 is used to measure the production of the oil well in different time periods during water flooding and polymer flooding.

Reservoir flow section division unit 108 is used to divide the reservoir into multiple flow sections according to the production of the oil wells in different time periods during the well test analysis of water flooding and polymer flooding. In the flow section, the well test analysis of water flooding and the well test analysis of polymer flooding are carried out sequentially.

The above examples introduce that on the basis of water flooding well test analysis, the single-phase oil in the multiphase fluid during water flooding is selected as the pseudo-single phase, and the pressure fitting is performed by modifying the viscosity in the parameters of the single-phase oil to obtain the pseudo-single phase. For the single-phase pseudo-viscosity, the oil-water two-phase model in the black oil model is selected, in which the single-phase oil is used as the oil phase, and the polymer solution is used as the water phase. Reservoir information is beneficial to the monitoring of the reservoir.

A kind of well test analysis method and device provided by the application have been introduced in detail above. The principle and implementation of the application have been explained by using specific examples in this paper. The description of the above examples is only used to help understand the application. method and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of this application, there will be changes in the specific implementation and application scope. Application Restrictions.

Claims (16)

1. A well testing analysis method, comprising:

measuring basic parameters of an oil well and fluids in each phase in the oil well;

performing water drive well testing analysis according to the oil well and basic parameters of each phase fluid in the oil well to obtain basic information of an oil reservoir during water drive;

selecting single-phase oil in multiphase flow during water flooding;

performing pressure fitting by using the basic information of the oil reservoir to obtain the pseudo-viscosity of the single-phase oil;

performing well test analysis of the polymer flooding by combining the pseudo-viscosity to obtain basic information of the oil reservoir during the polymer flooding;

and monitoring the oil reservoir information during the polymer flooding according to the basic information of the oil reservoir during the polymer flooding.

2. The method of claim 1, wherein the performing of water flooding well test analysis according to the oil well and the basic parameters of each phase fluid in the oil well, and the obtaining of the basic information of the reservoir during water flooding comprises:

measuring bottom hole actual pressure data during water flooding;

selecting a geological model, a shaft type and an oil reservoir boundary, and acquiring preset basic information of the oil reservoir during water flooding;

calculating and acquiring bottom hole flowing pressure during water flooding by using a black oil model according to basic parameters of an oil well and each phase fluid in the oil well, a geological model, a shaft type, an oil reservoir boundary and preset basic information of an oil reservoir;

and fitting the actual pressure data during water flooding with the bottom hole flowing pressure during water flooding obtained through calculation to obtain basic information of the oil reservoir during water flooding.

3. The method of claim 2, wherein the fitting the actual pressure data in the water flooding process and the bottom hole flowing pressure in the water flooding process obtained through calculation, and the obtaining of the basic information of the oil deposit in the water flooding process comprises:

acquiring actual pressure difference and pressure derivative during water flooding, and drawing a double-logarithmic graph of the pressure difference and the pressure derivative;

acquiring calculated pressure difference and pressure derivative during water flooding, and drawing a log-log graph of the pressure difference and the pressure derivative;

fitting the double logarithmic graphs of the actual pressure difference and pressure derivative in the water flooding process and the double logarithmic graphs of the calculated pressure difference and pressure derivative in the water flooding process, wherein if the fitting precision is within a preset precision range, the acquired basic oil reservoir information in the water flooding process is the required basic oil reservoir information; and if the fitting precision is not in the preset precision range, modifying preset basic information of the oil reservoir during water drive, and performing water drive well test analysis until the fitting precision is in the preset precision range.

4. The method of claim 1, wherein the pressure fitting using the base information of the reservoir to obtain the pseudo-viscosity of the single-phase oil comprises:

and changing the viscosity of the single-phase oil according to the basic information of the oil reservoir during water flooding, and performing well testing analysis to obtain the pseudo-viscosity of the single-phase fluid.

5. The method of claim 1, wherein the performing a well test analysis of the polymer flooding in combination with the pseudo-viscosity, and obtaining basic information of the reservoir at the time of the polymer flooding comprises:

selecting an oil-water two-phase model in a black oil model, wherein the water phase is a polymer solution, the viscosity of the water phase is the viscosity of the polymer solution, the oil phase is single-phase oil, the viscosity of the oil phase is pseudo-viscosity, and the basic parameters of the water phase and the oil phase are the basic parameters of the polymer solution and the single-phase oil;

measuring actual pressure data at polymer flooding;

selecting a geological model, a shaft type and an oil reservoir boundary, and acquiring preset basic information of the oil reservoir during polymer flooding;

calculating and acquiring bottom hole flowing pressure during polymer flooding by using a black oil model according to the basic parameters of the oil well, the basic parameters of the water phase fluid and the oil phase fluid, the geological model, the type of the shaft, the oil reservoir boundary and preset basic information of the oil reservoir during polymer flooding;

and fitting the actual pressure data during the polymer flooding with the bottom hole flowing pressure during the polymer flooding, which is obtained through calculation, so as to obtain the basic information of the oil reservoir during the polymer flooding.

6. The method of claim 5, wherein the fitting the actual pressure data at the time of the polymer flooding to the bottom hole flow pressure at the time of the polymer flooding is calculated, and the obtaining of the basic information of the reservoir at the time of the polymer flooding comprises:

acquiring actual pressure difference and pressure derivative during polymer flooding, and drawing a double-logarithmic graph of the pressure difference and the pressure derivative;

acquiring a calculated pressure difference and a pressure derivative during polymer flooding, and drawing a log-log graph of the pressure difference and the pressure derivative;

fitting the double logarithmic graphs of the actual pressure difference and pressure derivative during polymer flooding with the double logarithmic graphs of the calculated pressure difference and pressure derivative during polymer flooding, wherein if the fitting accuracy is within a preset accuracy range, the acquired basic oil reservoir information during polymer flooding is the required basic oil reservoir information; and if the fitting accuracy is not in the preset accuracy range, modifying preset basic information of the oil reservoir during the polymer flooding, and performing well testing analysis on the polymer flooding until the fitting accuracy is in the preset accuracy range.

7. The method according to any one of claims 1 to 6, wherein the basic parameters of the oil well and the fluids in each phase in the oil well comprise: the well, the viscosity of each phase fluid, the volume factor, the compressibility, the fluid density, the formation thickness, the porosity and the formation absolute permeability.

8. The method of any one of claims 1 to 6, wherein the basic information of the reservoir comprises: reservoir constant, wellbore skin, permeability, initial pressure, and virgin formation pressure.

9. A well testing analysis device, the device comprising:

the basic parameter measuring unit is used for measuring basic parameters of an oil well and fluids in each phase in the oil well;

the water-drive well testing analysis unit is used for carrying out water-drive well testing analysis according to the oil well and the basic parameters of each phase fluid in the oil well to obtain the basic information of the oil reservoir during water drive;

the quasi-single-phase flow acquisition unit is used for selecting single-phase oil in the multi-phase fluid during water flooding;

the pseudo-viscosity obtaining unit is used for carrying out pressure fitting by utilizing the basic information of the oil reservoir to obtain the pseudo-viscosity of the single-phase oil;

the polymer flooding well test analysis unit is used for carrying out polymer flooding well test analysis by combining the pseudo-viscosity to obtain basic information of an oil reservoir during polymer flooding;

and the monitoring unit is used for monitoring the oil well according to the basic information of the oil reservoir during the polymer flooding.

10. The apparatus of claim 9, wherein the water-driven well test analysis unit comprises:

the first measuring unit is used for measuring actual pressure data during water flooding;

the first selecting unit is used for selecting a geological model, a shaft type and an oil reservoir boundary in the water flooding process and acquiring preset basic information of the oil reservoir in the water flooding process;

the first calculation unit is used for calculating and acquiring the bottom hole flowing pressure in the water flooding process by utilizing the black oil model according to the oil well and the basic parameters of each phase of fluid in the oil well, the geological model, the shaft type, the oil reservoir boundary and the preset basic information of the oil reservoir;

and the first pressure fitting unit is used for fitting the actual pressure data during water flooding with the bottom hole flowing pressure during water flooding obtained through calculation to obtain the basic information of the oil reservoir during water flooding.

11. The apparatus of claim 10, wherein the first pressure fitting unit comprises:

the first logarithmic graph drawing unit is used for respectively obtaining actual and calculated pressure difference and pressure derivative during water flooding and drawing a double logarithmic graph of the pressure difference and the pressure derivative;

a first logarithmic graph fitting unit for fitting a log-log graph of actual pressure difference and pressure derivative at water flooding to a log-log graph of calculated pressure difference and pressure derivative at water flooding;

the first fitting precision judging unit is used for judging whether the fitting precision is within a preset precision range or not, and if the fitting precision is within the preset precision range, the acquired oil reservoir basic information during water flooding is required oil reservoir basic information; and if the fitting precision is not in the preset precision range, modifying preset basic information of the oil reservoir during water drive, and performing water drive well test analysis until the fitting precision is in the preset precision range.

12. The apparatus of claim 11, wherein the polymer flooding analysis unit comprises:

the second measuring unit is used for measuring the actual pressure data of the well bottom during polymer flooding;

the second selection unit is used for selecting a geological model, a shaft type and an oil reservoir boundary during polymer flooding and acquiring preset basic information of the oil reservoir during polymer flooding;

the second calculation unit is used for calculating and acquiring the bottom hole flowing pressure during polymer flooding by using the black oil model according to basic parameters of an oil well and the oil phase and water phase fluid, a geological model, a shaft type, an oil reservoir boundary and preset basic information of an oil reservoir;

and the second pressure fitting unit is used for fitting the actual pressure data during polymer flooding with the bottom hole flowing pressure during polymer flooding, which is obtained through calculation, so as to obtain the basic information of the oil reservoir during polymer flooding.

13. The apparatus of claim 12, wherein the second pressure fitting unit comprises:

the second logarithmic graph drawing unit is used for respectively acquiring actual and calculated pressure difference and pressure derivative during polymer flooding and drawing a double logarithmic graph of the pressure difference and the pressure derivative;

a second log fitting unit for fitting a log-log of the actual pressure difference and pressure derivative at polymer flooding to a log-log of the calculated pressure difference and pressure derivative at polymer flooding;

the second fitting precision judging unit is used for judging whether the fitting precision is within a preset precision range or not, and if the fitting precision is within the preset precision range, the acquired oil reservoir basic information during polymer flooding is required oil reservoir basic information; and if the fitting accuracy is not in the preset accuracy range, modifying preset basic information of the oil reservoir during the polymer flooding, and performing well testing analysis on the polymer flooding until the fitting accuracy is in the preset accuracy range.

14. The apparatus of claim 9, further comprising:

the oil well yield measuring unit is used for measuring the yield of the oil well in different time periods during water flooding and polymer flooding;

and the oil reservoir flowing section dividing unit is used for dividing the oil reservoir into a plurality of flowing sections according to the output of the oil well in different time periods during the water-drive well test analysis and the polymer-drive well test analysis, and sequentially carrying out the water-drive well test analysis and the polymer-drive well test analysis on the different flowing sections.

15. The apparatus of any one of claims 9 to 14, wherein the oil well and the essential parameters of the respective phase fluids in the oil well comprise: the well, the viscosity of each phase fluid, the volume factor, the compressibility, the fluid density, the formation thickness, the porosity and the formation absolute permeability.

16. The apparatus of any one of claims 9 to 14, wherein the basic information of the reservoir comprises: reservoir constant, wellbore skin, permeability, initial pressure, and virgin formation pressure.

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