CN103046925A - Binomial-based method and binomial-based system for acquiring absolute open-flow potential of condensate gas reservoir - Google Patents

Abstract

The invention relates to a binomial-based method and a binomial-based system for acquiring the absolute open-flow potential of condensate gas reservoir. The binomial-based method includes determining a binomial productivity equation under different formation pressures; acquiring relations among a first coefficient, a second coefficient, a third coefficient and a fourth coefficient of the binomial productivity equation via a first formation pressure, a second formation pressure, first natural gas viscosity, a first deviation coefficient, first gas-phase permeability, second natural gas viscosity, a second deviation coefficient and second gas-phase permeability according to the binomial productivity equation; and acquiring the absolute open-flow potential of the condensate gas reservoir under the different formation pressures according to the relations among the first coefficient, the second coefficient, the third coefficient and the fourth coefficient of the binomial productivity equation, known first absolute open-flow potential of the condensate gas reservoir, the known first formation pressure and the known second formation pressure. The first natural gas viscosity, the first deviation coefficient and the first gas-phase permeability correspond to the first formation pressure, and the second natural gas viscosity, the second deviation coefficient and the second gas-phase permeability correspond to the second formation pressure.

Description

Acquisition methods and system based on binomial gas condensate reservoir absolute open flow (AOF)

Technical field

The present invention relates to absolute open flow (AOF) and obtain the field, particularly based on acquisition methods and the system of gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure.

Background technology

Document 1: Chen Yuanqian, oil-gas reservoir engineering practice [M]. Beijing: petroleum industry publishing house, considered the impact of condensate on gas well deliverability in the method that 2005,142-146 proposes, be shown by formula table:

$P_e^2-{\mathrm{<figure-callout\; id="2"\; label="P\; wf"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">P</figure-callout>}}_{\mathrm{wf}}^{}={\mathrm{aq}}_{\mathrm{sc}}+{\mathrm{<figure-callout\; id="2"\; label="bq\; sc"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">bq</figure-callout>}}_{\mathrm{sc}}^{}$

Wherein: $a=\frac{{\mathrm{TZ\&mu;p}}_{\mathrm{sc}}}{\mathrm{\&pi;kh}{T}_{\mathrm{sc}}{Z}_{\mathrm{sc}}}(\ln \frac{r_e}{r_w}+S_c+S_b);$ $b=\frac{{\mathrm{\&beta;\&rho;}}_{\mathrm{<figure-callout\; id="2"\; label="sc"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">sc</figure-callout>}}}{{2\mathrm{\&pi;}}^2{h}^2}\frac{p_{\mathrm{sc}}\mathrm{TZ}}{Z_{\mathrm{sc}}{T}_{\mathrm{sc}}}\frac{1}{r_w{e}^{-s}}$ $S_b=(\frac{1}{k_{\mathrm{rgc}}}-1)\ln \frac{r_b}{r_w};$ P _eBe strata pressure, MPa, ρ are the natural gas relative density; P _WfBe flowing bottomhole pressure (FBHP), MPa, μ are Natural Gas Viscosity, mpas; Z is gas deviation factor, T _ScBe ground standard temperature, K; T is formation temperature, K; H is effective thickness, m; r _eBe gas well Control Radius, m, r _wBe Wellbore of Gas Wells radius, m; K is permeability, 10 ^-3μ m ², S _cBe the completion skin factor; A and b are binomial coefficient, S _bFor condensate blocks skin factor; r _bFor condensate blocks radius, m; β is non-Darcy seepage coefficient; K _RgcBe gas phase relative permeability under the critical condensate saturation ratio.

Document 2: Liao Huawei, Tanghai, Li Ning etc. determine the method [J] of gas well deliverability under the Different Strata pressure. the natural gas technology, 2008,16 (4): considered the impact of stratum pressure drop on gas well deliverability in the method that 30-32 proposes, be shown by formula table:

Exponential form: $q_{{\mathrm{AOF}}_2}=\frac{c_2}{c_1}{\left(\frac{p_{e2}}{p_{e1}}\right)}^{2n}$ $q_{{\mathrm{AOF}}_1}=\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_2}{\left(\frac{p_{e2}}{p_{e1}}\right)}^{2n}{q}_{\mathrm{AO}{\mathrm{<figure-callout\; id="1"\; label="F"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">F</figure-callout>}}_1}$

Binomial: $q_{\mathrm{AOF}2}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2}}\&CenterDot;q_{\mathrm{AOF}1}$

In the formula: a ₁, b ₁And a ₂, b ₂Be respectively the coefficient of binomial potential curve and equation, and corresponding Natural Gas Viscosity, deviation factor and gas phase permeability are respectively μ ₁, Z ₁, K ₁And μ ₂, Z ₂, K ₂P _E1And P _E2Be respectively the strata pressure of different mining phases.

Document 3: Zheng Likun, the Absolute Open Flow of Gas Wells Study on Forecasting Method [J] of consideration permeability stress sensitive. petroleum geology and engineering .2010,24 (2).

This article has been considered the reservoir permeability stress sensitive effect that strata pressure descends and causes, releases Absolute Open Flow of Gas Wells computational methods under the Different Strata pressure condition by binomial potential curve and equation.

$\frac{\mathrm{<figure-callout\; id="0"\; label="k\; k"\; filenames="HDA00002693053300051.png,HDA00002693053300061.png"\; state="\{\{state\}\}">k</figure-callout>}}{k_{}}={\mathrm{be}}^{\mathrm{ap}}$

$P_R^2-{\mathrm{<figure-callout\; id="2"\; label="P\; wf"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">P</figure-callout>}}_{\mathrm{wf}}^{}={\mathrm{Aq}}_g+{\mathrm{<figure-callout\; id="2"\; label="Bq\; g"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Bq</figure-callout>}}_g^{}$

${\mathrm{<figure-callout\; id="2"\; label="q\; AOF"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{AOF}}=\frac{P_{R2}}{P_{R1}}\sqrt{\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_{g1}{k}_2}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_{g2}{k}_1}}{q}_{\mathrm{AOF}1}=\frac{P_{R2}}{P_{R1}}\sqrt{\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_{g1}}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_{\mathrm{<figure-callout\; id="2"\; label="g"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">g</figure-callout>}2}}{\mathrm{be}}^{\mathrm{ap}}}{q}_{\mathrm{AOF}1}$

The deficiency of the method is that it is only applicable to common dry gas reservoir, can not be applied to gas condensate reservoir, because the calculating of permeability is based on the stress sensitive effect of rock in this piece article, and is not that condensate is separated out the reservoir gas phase permeability is exerted an influence.Although all considered the impact of permeability on result of calculation, the computational methods of permeability are the differences that essence is arranged under the both of these case.

By above documents and materials as can be known, according to the situation of change of pneumatic jack strata pressure, there are at present two kinds of equations to determine the absolute open flow (AOF) of gas well.The first, little if pressure changes, think that then the coefficient of Gas Well Productivity is constant on stream, can directly utilize early stage Gas Well Productivity; Second, consider that strata pressure changes the impact on aspects such as gas viscosity, deviation factors, derive gas well absolute open flow (AOF) under the Different Strata pressure by Gas Well Productivity, but present derivation is based on the constant precondition of reservoir permeability, and in the viscosity and deviation factor process of Calculation of Gas, think that the composition of gas is constant, namely molecular weight does not change.This hypothesis is set up for general dry gas reservoir, but then larger error of calculation can occur for gas condensate reservoir.

Summary of the invention

The objective of the invention is for the problems referred to above, propose a kind of acquisition methods and system based on binomial gas condensate reservoir gas recovery well absolute open flow (AOF), realize the effect that precision improves of obtaining of gas condensate reservoir gas recovery well absolute open flow (AOF).

For achieving the above object, the invention provides the acquisition methods of gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure, the method is based on the variation of gas composition in the gas condensate reservoir under the Different Strata pressure and variation the obtaining absolute open flow (AOF) of gas phase permeability; Comprise:

Determine binomial potential curve and equation under the Different Strata pressure;

According to described binomial potential curve and equation, by the first strata pressure and the second strata pressure and corresponding the first Natural Gas Viscosity, the first deviation factor and the first gas phase permeability of the first strata pressure, and corresponding the second Natural Gas Viscosity, the second deviation factor and the second gas phase permeability of the second strata pressure obtains the relation between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of binomial potential curve and equation;

Obtain gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure according to the relation between binomial potential curve and equation the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number, known the first gas condensate reservoir absolute open flow (AOF) and the first strata pressure and the second strata pressure.

Optionally, in an embodiment of the present invention, described gas phase permeability acquisition methods comprises:

According to etc. the appearance depletion experiments draw condensate content under the Different Strata pressure;

Obtain condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation;

Do not change the form that oil gas oozes curve mutually according to separating out of condensate, utilize oil gas to ooze mutually curve and obtain gas phase relative permeability under the different gas saturation with condensate saturation ratio under the Different Strata pressure;

Obtain gas phase permeability according to gas phase relative permeability and air absolute permeability.

Optionally, in an embodiment of the present invention, the described step that obtains the condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation comprises:

Obtain condensate saturation ratio under the Different Strata pressure according to following formula;

S _o(p)＝[V _roCVD(p)](1-S _wi)

Wherein, S _o(p) be condensate saturation ratio under the Different Strata pressure; S _WiBe irreducible water saturation; V _RoCVD(p) be condensate content under the Different Strata pressure.

Optionally, in an embodiment of the present invention, the described step of obtaining gas phase permeability according to gas phase relative permeability and air absolute permeability comprises:

Obtain gas phase permeability according to following formula;

K _rg=K/K _a

Wherein, K _RgBe the gas phase relative permeability; K _aFor the air absolute permeability, recorded by core experiment; K is gas phase permeability.

Optionally, in an embodiment of the present invention, the relation table between the first coefficient of described binomial potential curve and equation, the second coefficient, the 3rd coefficient and the Quaternary system number is shown:

$\frac{a_1}{a_2}=\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_1{K}_2}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{{\mathrm{<figure-callout\; id="2"\; label="b"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">b</figure-callout>}}_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2}$

Wherein, a ₁Be the first coefficient of binomial potential curve and equation, a ₂Be the second coefficient of binomial potential curve and equation, b ₁Be the 3rd coefficient of binomial potential curve and equation, b ₂Be the Quaternary system number of binomial potential curve and equation, Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, μ ₁Be the first Natural Gas Viscosity accordingly under the first strata pressure, μ ₂Be the second Natural Gas Viscosity accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂It is the second gas phase permeability accordingly under the second strata pressure.

Optionally, in an embodiment of the present invention, gas condensate reservoir absolute open flow (AOF) design formulas is under the described Different Strata pressure:

$q_{\mathrm{AO}{\mathrm{<figure-callout\; id="2"\; label="F"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">F</figure-callout>}}_2}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;q_{{\mathrm{AOF}}_1}$

Wherein,

Be gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure,

Be known gas condensate reservoir absolute open flow (AOF), Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂Be the second gas phase permeability accordingly under the second strata pressure, P _E1Be the first strata pressure, P _E2It is the second strata pressure.

For achieving the above object, the present invention also provides the system that obtains of gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure, and this system is based on the variation of gas composition in the gas condensate reservoir under the Different Strata pressure and variation the obtaining absolute open flow (AOF) of gas phase permeability; Comprise:

The binomial potential curve and equation determining unit is used for determining binomial potential curve and equation under the Different Strata pressure;

Binomial coefficient concerns determining unit, be used for according to described binomial potential curve and equation, by the first strata pressure and the second strata pressure and corresponding the first Natural Gas Viscosity, the first deviation factor and the first gas phase permeability of the first strata pressure, and corresponding the second Natural Gas Viscosity, the second deviation factor and the second gas phase permeability of the second strata pressure obtains the relation between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of binomial potential curve and equation;

The absolute open flow (AOF) acquiring unit is used for obtaining gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure according to the relation between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of binomial potential curve and equation, known gas condensate reservoir absolute open flow (AOF) and the first strata pressure and the second strata pressure.

Optionally, in an embodiment of the present invention, described binomial coefficient concerns that determining unit comprises:

Deng holding depleted module, be used for according to etc. the appearance depletion experiments draw condensate content under the Different Strata pressure;

Condensate saturation ratio acquisition module is used for obtaining condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation;

Relative permeability value acquisition module is used for not changing the form that oil gas oozes curve mutually according to separating out of condensate, utilizes oil gas to ooze mutually curve and obtains gas phase relative permeability under the different gas saturation with condensate saturation ratio under the Different Strata pressure;

The gas phase permeability acquisition module is used for obtaining gas phase permeability according to gas phase relative permeability and air absolute permeability.

Optionally, in an embodiment of the present invention, described condensate saturation ratio acquisition module obtains condensate saturation ratio under the Different Strata pressure according to following formula;

S _o(p)＝[V _roCVD(p)](1-S _wi)

Wherein, S _o(p) be condensate saturation ratio under the Different Strata pressure; S _WiBe irreducible water saturation; V _RoCVD(p) be condensate content under the Different Strata pressure.

Optionally, in an embodiment of the present invention, described gas phase permeability acquisition module obtains gas phase permeability according to following formula;

K _rg=K/K _a

Wherein, K _RgBe the gas phase relative permeability; K _aFor the air absolute permeability, recorded by core experiment; K is gas phase permeability.

Optionally, in an embodiment of the present invention, described binomial coefficient concerns that the relation table between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of the binomial potential curve and equation that determining unit is obtained is shown:

$\frac{a_1}{a_2}=\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_1{K}_2}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{{\mathrm{<figure-callout\; id="2"\; label="b"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">b</figure-callout>}}_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2}$

Wherein, a ₁Be the first coefficient of binomial potential curve and equation, a ₂Be the second coefficient of binomial potential curve and equation, b ₁Be the 3rd coefficient of binomial potential curve and equation, b ₂Be the Quaternary system number of binomial potential curve and equation, Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, μ ₁Be the first Natural Gas Viscosity accordingly under the first strata pressure, μ ₂Be the second Natural Gas Viscosity accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂It is the second gas phase permeability accordingly under the second strata pressure.

Optionally, in an embodiment of the present invention, the gas condensate reservoir absolute open flow (AOF) that described absolute open flow (AOF) acquiring unit obtains

Design formulas is:

${\mathrm{<figure-callout\; id="2"\; label="q\; AO\; F"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{AO}{F}_{}}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="q\; AOF"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{{\mathrm{AOF}}_{}}$

Wherein,

Be gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure,

Be known gas condensate reservoir absolute open flow (AOF), Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂Be the second gas phase permeability accordingly under the second strata pressure, P _E1Be the first strata pressure, P _E2It is the second strata pressure.

Technique scheme has following beneficial effect: because the technical scheme that the application proposes has considered that condensate is on the impact of gas phase permeability and the variation of condensate gas component, more accurate to obtaining of absolute open flow (AOF), in order to instruct the reasonable effective exploitation of gas condensate reservoir.

Description of drawings

In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art, apparently, accompanying drawing in the following describes only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the acquisition methods flow chart based on gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure that the present invention proposes;

Fig. 2 is the system construction drawing that obtains based on gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure that the present invention proposes;

Fig. 3 be the present invention propose obtain based on gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure that binomial coefficient concerns the determining unit structure chart in the system;

Fig. 4 is that the mixture molecular weight is with the change curve of pressure;

Fig. 5 is that gas phase permeability is with the change curve of pressure;

Fig. 6 is that binomial gas condensate reservoir absolute open flow (AOF) is with the change curve of strata pressure;

Fig. 7 is the acquisition methods flow chart of the gas phase permeability that proposes of the present invention.

The implementation equation

Below in conjunction with the accompanying drawing in the embodiment of the invention, the technical scheme in the embodiment of the invention is clearly and completely described.Obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that obtains under the creative work prerequisite.

Gas condensate reservoir is a kind of special, complicated gas reservoir.On stream, condensate gas well presents different flow regions with the decline of strata pressure, and different flow regions is just followed different seepage flow equations.Obtain zones of different accurately oil gas branch to ooze mutually curve with corresponding oil gas be very difficult, the application is on the basis of labor and constantly trial, adopt approximate gas phase permeability computational methods, obtained preferably effect, reduce error of calculation, satisfied the requirement of engineering calculation precision.

As shown in Figure 1, for the present invention propose based on one of the acquisition methods flow chart of gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure, the method is based on the variation of gas composition in the gas condensate reservoir under the Different Strata pressure and variation the obtaining absolute open flow (AOF) of gas phase permeability; Comprise:

Step 101: determine binomial potential curve and equation under the Different Strata pressure.

Step 102: according to described binomial potential curve and equation, by strata pressure P _E1And P _E2And strata pressure P _E1Corresponding Natural Gas Viscosity μ ₁, deviation factor Z ₁With gas phase permeability K ₁, and strata pressure P _E2Corresponding Natural Gas Viscosity μ ₂, deviation factor Z ₂With gas phase permeability K ₂Obtain binomial potential curve and equation coefficient a ₁, a ₂, b ₁And b ₂Between relation.

Step 103: according to binomial potential curve and equation coefficient a ₁, a ₂, b ₁And b ₂Between relation, known gas condensate reservoir absolute open flow (AOF)

And strata pressure P _E1And P _E2Obtain gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure

The acquisition methods flow chart of the gas phase permeability that proposes for the present invention as shown in Figure 7.Comprise:

Step a: according to etc. the appearance depletion experiments draw condensate content under the Different Strata pressure;

Step b: obtain condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation;

Step c: do not change the form that oil gas oozes curve mutually according to separating out of condensate, utilize oil gas to ooze mutually curve and obtain gas phase relative permeability under the different gas saturation with condensate saturation ratio under the Different Strata pressure;

Steps d: obtain gas phase permeability according to gas phase relative permeability and air absolute permeability.

Optionally, in an embodiment of the present invention, the described step that obtains the condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation comprises:

Obtain condensate saturation ratio under the Different Strata pressure according to following formula;

S _o(p)＝[V _roCVD(p)](1-S _wi)

Wherein, S _o(p) be condensate saturation ratio under the Different Strata pressure; S _WiBe irreducible water saturation; V _RoCVD(p) be condensate content under the Different Strata pressure.

Optionally, in an embodiment of the present invention, the described step of obtaining gas phase permeability according to gas phase relative permeability and air absolute permeability comprises:

Obtain gas phase permeability according to following formula;

K _rg=K/K _a

Wherein, K _RgBe the gas phase relative permeability; K _aFor the air absolute permeability, recorded by core experiment; K is gas phase permeability.

Optionally, in an embodiment of the present invention, described binomial potential curve and equation coefficient a ₁, a ₂, b ₁And b ₂Between relation table be shown:

$\frac{a_1}{a_2}=\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_1{K}_2}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{b_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2}.$

Optionally, in an embodiment of the present invention, described gas condensate reservoir absolute open flow (AOF)

Design formulas is:

${\mathrm{<figure-callout\; id="2"\; label="q\; AO\; F"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{AO}{F}_{}}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="q\; AOF"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{{\mathrm{AOF}}_{}}.$

As shown in Figure 2, obtain one of system construction drawing for what the present invention proposed based on gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure.This system is based on the variation of gas composition in the gas condensate reservoir under the Different Strata pressure and variation the obtaining absolute open flow (AOF) of gas phase permeability; Comprise:

Binomial potential curve and equation determining unit 201 is used for determining binomial potential curve and equation under the Different Strata pressure;

Binomial coefficient concerns determining unit 202, is used for according to described binomial potential curve and equation, by strata pressure P _E1And P _E2And strata pressure P _E1Corresponding Natural Gas Viscosity μ ₁, deviation factor Z ₁With gas phase permeability K ₁, and strata pressure P _E2Corresponding Natural Gas Viscosity μ ₂, deviation factor Z ₂With gas phase permeability K ₂Obtain binomial potential curve and equation coefficient a ₁, a ₂, b ₁And b ₂Between relation;

Absolute open flow (AOF) acquiring unit 203 is used for according to binomial potential curve and equation coefficient a ₁, a ₂, b ₁And b ₂Between relation, known gas condensate reservoir absolute open flow (AOF)

And strata pressure P _E1And P _E2Obtain gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure

As shown in Figure 3, obtain based on gas condensate reservoir absolute open flow (AOF) under the binomial Different Strata pressure that binomial coefficient concerns the determining unit structure chart in the system for what the present invention proposed.Described binomial coefficient concerns that determining unit 202 comprises:

Deng holding depleted module 2021, be used for according to etc. the appearance depletion experiments draw condensate content under the Different Strata pressure;

Condensate saturation ratio acquisition module 2022 is used for obtaining condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation;

Relative permeability value acquisition module 2023 is used for not changing the form that oil gas oozes curve mutually according to separating out of condensate, utilizes oil gas to ooze mutually curve and obtains gas phase relative permeability under the different gas saturation with condensate saturation ratio under the Different Strata pressure;

Gas phase permeability acquisition module 2024 is used for obtaining gas phase permeability according to gas phase relative permeability and air absolute permeability.

Optionally, in an embodiment of the present invention, described condensate saturation ratio acquisition module 2022 obtains condensate saturation ratio under the Different Strata pressure according to following formula;

S _o(p)＝[V _roCVD(p)](1-S _wi)

Wherein, S _o(p) be condensate saturation ratio under the Different Strata pressure; S _WiBe irreducible water saturation; V _RoCVD(p) be condensate content under the Different Strata pressure.

Optionally, in an embodiment of the present invention, described gas phase permeability acquisition module 2024 obtains gas phase permeability according to following formula;

K _rg=K/K _a

Wherein, K _RgBe the gas phase relative permeability; K _aFor the air absolute permeability, recorded by core experiment; K is gas phase permeability.

Optionally, in an embodiment of the present invention, described binomial coefficient concerns the binomial potential curve and equation coefficient a that determining unit 202 is obtained ₁, a ₂, b ₁And b ₂Between relation table be shown:

$\frac{a_1}{a_2}=\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_1{K}_2}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{b_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2}.$

Optionally, in an embodiment of the present invention, the gas condensate reservoir absolute open flow (AOF) that described absolute open flow (AOF) acquiring unit 203 obtains Design formulas is:

${\mathrm{<figure-callout\; id="2"\; label="q\; AO\; F"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{AO}{F}_{}}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="q\; AOF"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{{\mathrm{AOF}}_{}}.$

The device that the present invention proposes is for utilizing general processor, digital signal processor, special IC (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, computer installation, or circuit load distribution in the distribution network automated device realized of the design of above-mentioned any combination, do not need main website and substation and complicated communication device.

Those skilled in the art can also recognize that various illustrative components, blocks (illustrative logical block), unit and the step listed in the device of the present invention can pass through electronic hardware, computer software, or both combinations realize.Be the clear replaceability (interchangeability) of showing hardware and software, above-mentioned various illustrative components (illustrative components), unit and step have been described their function generally.Such function is to realize depending on the designing requirement of specific application and whole device by hardware or software.Those skilled in the art can be for every kind of specific application, and can make ins all sorts of ways realizes described function, but this realization should not be understood to exceed the scope of embodiment of the invention protection.

Various illustrative logical block described in the device of the present invention, or the unit can pass through general processor, digital signal processor, special IC (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the design of above-mentioned any combination realizes or operates described function.General processor can be microprocessor, and alternatively, this general processor also can be any traditional processor, controller, microcontroller or state machine.Processor also can realize by the combination of calculation element, for example digital signal processor and microprocessor, multi-microprocessor, Digital Signal Processor Core of one or more microprocessors associatings, or any other similarly configuration realize.

Method described in the device of the present invention or the step of algorithm can directly embed hardware, the software module of processor execution or the two combination.Software module can be stored in the storage medium of other arbitrary form in RAM memory, flash memory, ROM memory, eprom memory, eeprom memory, register, hard disk, moveable magnetic disc, CD-ROM or this area.Exemplarily, storage medium can be connected with processor so that processor can be from storage medium reading information, and can deposit write information to storage medium.Alternatively, storage medium can also be integrated in the processor.Processor and storage medium can be arranged among the ASIC, and ASIC can be arranged in the user terminal.Alternatively, processor and storage medium also can be arranged in the different parts in the user terminal.

In one or more exemplary designs, the above-mentioned functions described in the device of the present invention can realize in hardware, software, firmware or this three's any combination.If realize in software, these functions can be stored on the medium with computer-readable, or are transmitted on the medium of computer-readable with one or more instructions or code form.The computer-readable medium comprises the computer storage medium and is convenient to so that allow computer program transfer to other local telecommunication media from a place.Storage medium can be the useable medium that any general or special computer can access.For example, such computer readable media can include but not limited to RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage device, or other anyly can be used for carrying or storage can be read by general or special computer or general or special processor the program code of form with instruction or data structure and other medium.In addition, any connection can suitably be defined as the computer-readable medium, for example, if software is by a coaxial cable, fiber optic cables, twisted-pair feeder, Digital Subscriber Line (DSL) or with also being comprised in the defined computer-readable medium such as the wireless equation transmission such as infrared, wireless and microwave from a web-site, server or other remote resource.Described video disc (disk) and disk (disc) comprise Zip disk, radium-shine dish, CD, DVD, floppy disk and Blu-ray Disc, and disk is usually with the magnetic duplication data, and video disc carries out the optical reproduction data with laser usually.Above-mentioned combination also can be included in the computer-readable medium.

For gas condensate reservoir, after strata pressure dropped to below the dew-point pressure, the heavy component in the condensate gas gradually retrograde condensation caused the composition of condensate gas to change in the stratum, retrograde condensation condensate out can adsorb rock surface simultaneously, affects the Reservoir Seepage kinetic force.Inquired into the technical scheme that the gas condensate reservoir absolute open flow (AOF) is obtained under the Different Strata pressure in the embodiment of the invention, descend on the impact of gas phase permeability and condensate gas composition by the research strata pressure, utilize binomial potential curve and equation and exponential deliverability equation, can derive the Gas Well Productivity of gas condensate reservoir under Different Strata pressure, in order to instruct the reasonable effective exploitation of gas condensate reservoir.

Main difference for gas condensate reservoir and dry gas reservoir is following two aspects: the first, and the variation of gas composition.As shown in Figure 4, be the change curve of mixture molecular weight with pressure; The second, the variation of gas phase permeability.As shown in Figure 5, be the change curve of gas phase permeability with pressure.Wherein, the gas composition variation is mainly manifested in the variation of admixture of gas molecular weight the impact of production capacity.According to existing gas testing data, utilize mathematical method just can draw the molecular weight of gas under the Different Strata pressure.When condensate was separated out from gas, the permeability of gas phase can change, and oozed mutually curve and just can draw gas phase permeability under the different gas saturation according to what experiment drew.

In this application, the acquisition methods of gas phase permeability under the Different Strata pressure:

The change of gas phase permeability K is because separating out of condensate given birth to impact to the vapor phase stream movable property, and this is the special properties decision of gas condensate reservoir, but not the permeability that stress sensitive causes changes.

Experiment can draw the condensate content under the Different Strata pressure according to CVD, at this moment oil, gas, water three-phase, irreducible water saturation S can occur in the blowhole _WiCan be obtained by measured data, by formula S _o(p)=[V _RoCVD(p)] (1-S _Wi) can obtain the condensate saturation ratio S under the Different Strata pressure _o(p).Suppose that separating out of condensate do not change the form that oil gas oozes curve mutually, ooze mutually condensate saturation ratio under curve and the Different Strata pressure according to oil gas, can obtain the relative permeability value of oil phase and gas phase under the different gas saturation.

In existing numerous methods of obtaining gas phase permeability, for gas condensate reservoir, have following features:

A): be difficult to obtain that oil gas oozes curve mutually under the actual formation state;

B): according to the rock core information of reality, in the laboratory, can obtain oil gas and ooze mutually curve;

C): this oozes mutually curve and has reflected oil gas two phase fluid flow characteristics, draws condensate content under the Different Strata pressure by CVD experiment again, just can approximate calculation goes out the gas phase permeability under the Different Strata pressure.In a word, the method can utilize limited condition to obtain being similar to the flow effect of oil gas two-phase under the layer state truly, has significantly reduced the error of calculation of gas condensate reservoir Absolute Open Flow of Gas Wells.

Embodiment:

According to binomial potential curve and equation: $P_e^2-{\mathrm{<figure-callout\; id="2"\; label="P\; wf"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">P</figure-callout>}}_{\mathrm{wf}}^{}={\mathrm{aq}}_{\mathrm{sc}}+{\mathrm{bq}}_{\mathrm{<figure-callout\; id="2"\; label="sc"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">sc</figure-callout>}}^2;$

Suppose that strata pressure is respectively P at two different mining phases _E1And P _E2, the coefficient of binomial potential curve and equation is respectively a ₁, b ₁And a ₂, b ₂, and corresponding Natural Gas Viscosity, deviation factor and gas phase permeability are respectively μ ₁, Z ₁, K ₁And μ ₂, Z ₂, K ₂, then can obtain following relation:

$\frac{a_1}{a_2}=\frac{{\mathrm{<figure-callout\; id="1"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_1{\mathrm{\&mu;}}_1{K}_2}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{b_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2};$

According to binomial potential curve and equation coefficient a ₁, a ₂, b ₁And b ₂Between relation, known gas condensate reservoir absolute open flow (AOF)

And strata pressure P _E1And P _E2Obtain gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure

${\mathrm{<figure-callout\; id="2"\; label="q\; AOF"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{AOF}}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="q\; AOF"\; filenames="HDA00002693053300061.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{AOF}}$

As shown in Figure 6, among the embodiment based on the change curve of binomial gas condensate reservoir absolute open flow (AOF) with strata pressure.E curve among Fig. 6 is not considered condensate to the impact of reservoir permeability and molecular weight gas, and the F curve considers that simultaneously the stratum pressure drop is on the impact of molecular weight gas and reservoir permeability.As can be seen from the figure, when strata pressure drops to dew-point pressure when following, consider condensate to the impact of gas phase permeability and the variation of condensate gas component, result of calculation is more accurate.

By calculating end value as can be known in the following table 1, according to the actual gas testing data in certain oil field and the detection analysis report of this well, adopt common dry gas reservoir computational methods and calculate respectively the absolute open flow (AOF) of gas well based on gas condensate reservoir computational methods under the binomial Different Strata pressure.Its result of calculation shows, the gas well output that the computational methods of employing dry gas reservoir are calculated gas condensate reservoir all larger error can occur, surpassed the required precision (0-10%) of engineering calculation, and greatly reduce error of calculation based on gas condensate reservoir Square rule under the binomial Different Strata pressure, the method satisfied the required precision of engineering calculation, so can well instruct the production in oil field.

Table 12007 year binomial result of calculation of Q1 well and error

Above-described implementation equation; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is implementation equation of the present invention; the protection domain that is not intended to limit the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (12)

1. the acquisition methods of gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure is characterized in that, the method is based on the variation of gas composition in the gas condensate reservoir under the Different Strata pressure and variation the obtaining absolute open flow (AOF) of gas phase permeability; Comprise:

Determine binomial potential curve and equation under the Different Strata pressure;

According to described binomial potential curve and equation, by the first strata pressure and the second strata pressure and corresponding the first Natural Gas Viscosity, the first deviation factor and the first gas phase permeability of the first strata pressure, and corresponding the second Natural Gas Viscosity, the second deviation factor and the second gas phase permeability of the second strata pressure obtains the relation between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of binomial potential curve and equation;

Obtain gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure according to the relation between binomial potential curve and equation the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number, known the first gas condensate reservoir absolute open flow (AOF) and the first strata pressure and the second strata pressure.

2. method according to claim 1 is characterized in that, described gas phase permeability acquisition methods comprises:

According to etc. the appearance depletion experiments draw condensate content under the Different Strata pressure;

Obtain condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation;

Do not change the form that oil gas oozes curve mutually according to separating out of condensate, utilize oil gas to ooze mutually curve and obtain gas phase relative permeability under the different gas saturation with condensate saturation ratio under the Different Strata pressure;

Obtain gas phase permeability according to gas phase relative permeability and air absolute permeability.

3. method according to claim 1 and 2 is characterized in that, the described step that obtains the condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation comprises:

Obtain condensate saturation ratio under the Different Strata pressure according to following formula;

S _o(p)＝[V _roCVD(p)](1-S _wi)

Wherein, S _o(p) be condensate saturation ratio under the Different Strata pressure; S _WiBe irreducible water saturation; V _RoCVD(p) be condensate content under the Different Strata pressure.

4. method according to claim 2 is characterized in that, the described step of obtaining gas phase permeability according to gas phase relative permeability and air absolute permeability comprises:

Obtain gas phase permeability according to following formula;

K _rg=K/K _a

Wherein, K _RgBe the gas phase relative permeability; K _aFor the air absolute permeability, recorded by core experiment; K is gas phase permeability.

5. the described method of arbitrary claim is characterized in that according to claim 1 ~ 4, and the relation table between the first coefficient of described binomial potential curve and equation, the second coefficient, the 3rd coefficient and the Quaternary system number is shown:

$\frac{a_1}{a_2}=\frac{Z_1{\mathrm{\&mu;}}_1{K}_2}{Z_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{b_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{Z_2}$

Wherein, a ₁Be the first coefficient of binomial potential curve and equation, a ₂Be the second coefficient of binomial potential curve and equation, b ₁Be the 3rd coefficient of binomial potential curve and equation, b ₂Be the Quaternary system number of binomial potential curve and equation, Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, μ ₁Be the first Natural Gas Viscosity accordingly under the first strata pressure, μ ₂Be the second Natural Gas Viscosity accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂It is the second gas phase permeability accordingly under the second strata pressure.

6. the described method of arbitrary claim is characterized in that according to claim 1 ~ 4, and gas condensate reservoir absolute open flow (AOF) design formulas is under the described Different Strata pressure:

$q_{\mathrm{AO}{F}_2}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;q_{{\mathrm{AOF}}_1}$

Wherein,

Be gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure,

Be known gas condensate reservoir absolute open flow (AOF), Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂Be the second gas phase permeability accordingly under the second strata pressure, P _E1Be the first strata pressure, P _E2It is the second strata pressure.

7. the system that obtains of gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure is characterized in that, this system is based on the variation of gas composition in the gas condensate reservoir under the Different Strata pressure and variation the obtaining absolute open flow (AOF) of gas phase permeability; Comprise:

The binomial potential curve and equation determining unit is used for determining binomial potential curve and equation under the Different Strata pressure;

Binomial coefficient concerns determining unit, be used for according to described binomial potential curve and equation, by the first strata pressure and the second strata pressure and corresponding the first Natural Gas Viscosity, the first deviation factor and the first gas phase permeability of the first strata pressure, and corresponding the second Natural Gas Viscosity, the second deviation factor and the second gas phase permeability of the second strata pressure obtains the relation between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of binomial potential curve and equation;

The absolute open flow (AOF) acquiring unit is used for obtaining gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure according to the relation between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of binomial potential curve and equation, known gas condensate reservoir absolute open flow (AOF) and the first strata pressure and the second strata pressure.

8. system according to claim 7 is characterized in that, described binomial coefficient concerns that determining unit comprises:

Deng holding depleted module, be used for according to etc. the appearance depletion experiments draw condensate content under the Different Strata pressure;

Condensate saturation ratio acquisition module is used for obtaining condensate saturation ratio under the Different Strata pressure according to the condensate content under the Different Strata pressure and irreducible water saturation;

Relative permeability value acquisition module is used for not changing the form that oil gas oozes curve mutually according to separating out of condensate, utilizes oil gas to ooze mutually curve and obtains gas phase relative permeability under the different gas saturation with condensate saturation ratio under the Different Strata pressure;

The gas phase permeability acquisition module is used for obtaining gas phase permeability according to gas phase relative permeability and air absolute permeability.

9. system according to claim 8 is characterized in that, described condensate saturation ratio acquisition module obtains condensate saturation ratio under the Different Strata pressure according to following formula;

S _o(p)＝[V _roCVD(p)](1-S _wi)

Wherein, S _o(p) be condensate saturation ratio under the Different Strata pressure; S _WiBe irreducible water saturation; V _RoCVD(p) be condensate content under the Different Strata pressure.

10. system according to claim 8 is characterized in that, described gas phase permeability acquisition module obtains gas phase permeability according to following formula;

K _rg=K/K _a

Wherein, K _RgBe the gas phase relative permeability; K _aFor the air absolute permeability, recorded by core experiment; K is gas phase permeability.

11. the described system of arbitrary claim is characterized in that according to claim 7 ~ 10, described binomial coefficient concerns that the relation table between the first coefficient, the second coefficient, the 3rd coefficient and the Quaternary system number of the binomial potential curve and equation that determining unit is obtained is shown:

$\frac{a_1}{a_2}=\frac{Z_1{\mathrm{\&mu;}}_1{K}_2}{Z_2{\mathrm{\&mu;}}_2{K}_1}\frac{b_1}{b_2}={\left(\frac{K_2}{K_1}\right)}^{1.1045}\frac{Z_1}{Z_2}$

Wherein, a ₁Be the first coefficient of binomial potential curve and equation, a ₂Be the second coefficient of binomial potential curve and equation, b ₁Be the 3rd coefficient of binomial potential curve and equation, b ₂Be the Quaternary system number of binomial potential curve and equation, Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, μ ₁Be the first Natural Gas Viscosity accordingly under the first strata pressure, μ ₂Be the second Natural Gas Viscosity accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂It is the second gas phase permeability accordingly under the second strata pressure.

12. the described system of arbitrary claim is characterized in that according to claim 7 ~ 10, the gas condensate reservoir absolute open flow (AOF) that described absolute open flow (AOF) acquiring unit obtains

Design formulas is:

$q_{\mathrm{AO}{F}_2}=\frac{p_{e2}}{p_{e1}}\sqrt{\frac{Z_1}{Z_2}}{\left(\frac{K_2}{Z_2}\right)}^{0.5502}\&CenterDot;q_{{\mathrm{AOF}}_1}$

Wherein, Be gas condensate reservoir absolute open flow (AOF) under the Different Strata pressure, Be known gas condensate reservoir absolute open flow (AOF), Z ₁Be the first deviation factor accordingly under the first strata pressure, Z ₂Be the second deviation factor accordingly under the second strata pressure, K ₁Be the first gas phase permeability accordingly under the first strata pressure, K ₂Be the second gas phase permeability accordingly under the second strata pressure, P _E1Be the first strata pressure, P _E2It is the second strata pressure.

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