CN102953726B - Method and device for water drive oilfield advantage channel recognition - Google Patents

Abstract

The invention discloses a method and a device for water drive oilfield advantage channel recognition. Unstable pressure restore well testing data are applied to recognize advantage channels formed during development of water drive oilfields. The method includes: step of setting a well testing typical characteristic curve layout, step of calculating well testing bottom pressure derivatives, step of drawing a testing well relation curve and step of judging existence and development level of the advantage channels, and the device comprises a typical characteristic curve layout setting module, a well bottom pressure measuring module, a well bottom pressure derivative calculation module, a testing well relation curve drawing module and a judging module. Compared with the prior art, the method for water drive oilfield advantage channel recognition is high in accuracy, high in generality, easy to implement, high in operability and capable of providing technical support for implementation of subsequent oilfield yield-increasing measures and designing of recovery ratio improving schemes.

Description

A kind of water controlled field advantage channel recognition method and device

Technical field

The present invention relates to the recognition technology of water controlled field advantage passage, particularly a kind of water controlled field advantage channel recognition method and device that utilizes transient well test method to identify the advantage passage forming in water controlled field development process.

Background technology

In the long-term injecting water development process in oil field, RESERVOIR PORE STRUCTURE can great changes will take place.The variation of the Development Factors such as the geologic(al) factors such as reservoir heterogeneity, exploitation rate are too fast and formation pressure etc. all can make reservoir pore throat radius increase, and permeability increases, thereby in reservoir, forms secondary high permeable strip, i.e. advantage passage.In oilfield development process, the most responsive development parameters of advantage passage is pressure and output, and the data that well testing is enrolled is unique data of enrolling under reservoir fluid flow regime in various data, therefore analysis result also can represent the dynamic characteristic of oil-gas reservoir.Because advantage passage forms gradually in oilfield development process, therefore the growth rank of advantage passage is not unalterable, but a dynamic changing process growing from weak to strong.The flow regime of advantage inner fluid passage also gradually changes, and is evolved into gradually non-darcy flow from darcy flow.The appearance of advantage passage will cause the poor efficiency of great amount of injection water, invalid circulation, and the non-homogeneity that its has on the one hand aggravated oil reservoir has reduced the sweep efficiency of injected water, has reduced injected water utilization rate; Aggravated on the other hand layer interior, an interlayer contradiction, the fuel-displaced situation of water suction of other oil reservoir of severe jamming, causes well water to rise fast, and water drive development degree is low; Meanwhile, it also can cause other well stimulation to implement more difficult, strengthens the workload of gathering line and multi-purpose station, and oil field development cost is increased, and has reduced the economic recovery in oil field, affects the raising of oil field development benefit.

Therefore, how effectively to identify advantage passage and choose suitable technological measure it is administered, increasing injected water sweep efficiency with this, improving oilfield water flooding development effectiveness, having become the major issue of being badly in need of solution in middle High Water Cut Reservoir exploitation.And the crucial and primary work addressing this problem is exactly accurately and effectively advantage passage to be identified.Conventional advantage channel recognition method mainly contains at present: interwell tracer test method, logging method, hydraulic detection method and reservoir engineering method.Tracer method mainly by detection inject tracer well around responding well tracer output concentration over time, utilize analytic method or method for numerical simulation, simulate concentration curve, by adjusting formation parameter, utilize parameter to change the feature of carrying out simulate formation advantage passage; The water suction situation of change of each substratum is mainly determined in logging method according to the abnormal response of well-log information, and then substantially determines the layer position that has abnormal water absorption because of advantage passage; The variation that hydraulic detection method mainly utilizes compression wave to be passed to the change interpretation oil-yielding stratum permeability of pressure reduction between required time of producing well and well by water injection well, and then quantitative interpretation goes out the parameter of advantage passage; Reservoir engineering method is mainly by the mobile one dimensional flow that is considered as of water in advantage passage, the Mathematical Modeling after setting up macropore and forming, and then adopt stream-tube method to calculate the parameter of advantage passage.But existing advantage channel recognition theoretical method basis imperfection, the hypothesis based on darcy flow or pipe stream only often in the time setting up Mathematical Modeling, do not consider the corresponding different seepage states of different stage advantage passage and the impact on advantage channel recognition thereof, can not accurately reflect the feature of advantage passage; In addition, tracer test and hydraulic detection method somewhat expensive, and also the qualitative composition of parameter interpretation process is more, affected by force by artificial subjectivity, operability is weak, be unfavorable for field conduct; The layer position that logging method can qualitative discrimination advantage passage exists, but cannot judge the rank that advantage passage is grown, awareness is lower, and in test process, can affect the normal production in oil field, and cost is higher; Reservoir engineering method is with Guan Liuwei basic model, calculates simplely, but hypothesis is too idealized, does not meet the actual conditions of advantage passage.

Therefore, the recognition methods of research different stage advantage passage, has important theory and realistic meaning for the exploitation of middle High Water Cut Reservoir.

Summary of the invention

Technical problem to be solved by this invention is to provide that a kind of accuracy is high, highly versatile and the simple advantage passage to forming in water controlled field development process are known method for distinguishing and device.

To achieve these goals, the invention provides a kind of water controlled field advantage channel recognition method, wherein, application transient pressure recovers well test data to be identified the advantage passage forming in water controlled field development process, comprises the steps:

A, well testing characteristic feature curve plate step is set: the well testing characteristic feature curve plate that advantage channel recognition is set;

B, well testing bottom hole pressure measurement step: pressure gauge is lowered to well testing test purpose layer middle part, and surface shut-in, utilizes pressure gauge to record the information well bottom pressure that well testing bottom pressure recovered with the testing time;

C, well testing bottom pressure derivative calculations step: the bottom pressure that calculates described well testing to the first derivative of time natural logrithm as bottom pressure derivative;

D, draw actual measurement well testing relation curve step: take the testing time as abscissa, take flowing bottomhole pressure (FBHP) and pressure derivative as ordinate, in log-log coordinate system, draw described bottom pressure or the time dependent actual measurement well testing of described bottom pressure derivative relation curve;

E, judge the existence of advantage passage and grow rank step: the described well testing characteristic feature curve of described actual measurement well testing relation curve and advantage channel recognition is carried out to form comparison, judge whether advantage passage exists and determine its growth rank.

Above-mentioned water controlled field advantage channel recognition method, wherein, before described drafting actual measurement well testing relation curve step, also comprises:

D0, data smoothing treatment step: described bottom pressure or described bottom pressure derivative and the relation of time are carried out to data smoothing processing to reduce noise.

Above-mentioned water controlled field advantage channel recognition method, wherein, described data smoothing treatment step adopts Wavelet Transform, linear interpolation exponential smoothing or Fourier transform to carry out data smoothing processing to described bottom pressure or described bottom pressure derivative.

Above-mentioned water controlled field advantage channel recognition method, wherein, the described well testing characteristic feature curve plate step that arranges comprises and normal reservoir well test curve plate is set and advantage passage well testing characteristic feature curve plate is set.

Above-mentioned water controlled field advantage channel recognition method, wherein, described normal reservoir well test curve plate is the transient seepage flow model curve plate of center, the infinitely great stratum of homogeneous a bite well.

Above-mentioned water controlled field advantage channel recognition method, wherein, the described advantage passage well testing characteristic feature curve plate that arranges comprises:

A1, setting models assumed condition: according to the assumed condition of the origin cause of formation of advantage passage and growth rank setting models;

A2, set up Mathematical Modeling: set up respectively corresponding Mathematical Modeling according to the origin cause of formation of described advantage passage and the assumed condition of growing rank;

A3, model solution and characteristic feature Drawing of Curve: respectively described Mathematical Modeling solved and draw corresponding advantage passage well testing characteristic feature curve plate according to solving result.

Above-mentioned water controlled field advantage channel recognition method, wherein, described advantage passage well testing characteristic feature curve plate grows from weak to strong according to the origin cause of formation of advantage passage and growth rank, comprises common high permeability zone indicatrix plate, strong high infiltration strip indicatrix plate and macropore indicatrix plate.

In order to realize better above-mentioned purpose, the present invention also provides a kind of water controlled field advantage passage identification device, and wherein, application transient pressure recovers well test data to be identified the advantage passage forming in water controlled field development process, comprising:

Characteristic feature curve plate module is set: for arranging and store the well testing characteristic feature curve plate of advantage channel recognition;

Bottom hole pressure measurement module: comprise pressure gauge and pressure record unit, the bottom pressure that described pressure gauge recovers with the testing time for testing well testing, and the described bottom pressure that test is obtained is conveyed into described pressure record unit;

Bottom pressure derivative calculations module: for calculating the first derivative of described bottom pressure to time natural logrithm, as bottom pressure derivative and store this bottom pressure derivative;

Draw well testing relation curve module: for drawing described bottom pressure or the time dependent actual measurement well testing of described bottom pressure derivative relation curve in log-log coordinate system;

Judge module: for the described well testing characteristic feature curve of described actual measurement well testing relation curve and advantage channel recognition is carried out to form comparison, judge advantage passage whether exist and determine its grow rank.

Above-mentioned water controlled field advantage passage identification device, wherein, also comprises:

Data smoothing processing module: for described bottom pressure or described bottom pressure derivative and the relation of time are carried out data smoothing process after the described drafting actual measurement of input well testing relation curve module.

Technique effect of the present invention is: the present invention is on the basis of transient well test test, by the theory analysis to different stage advantage passage seepage characteristics, draw the characteristic feature curve for different stage advantage passage, set up a set of new method of identifying accurately and effectively water controlled field advantage passage.The present invention is through field conduct, and the checking of carrying out with routine techniques, has all obtained good effect.This technology is compared with routine techniques, and accuracy is high, highly versatile, simple, has stronger operability, can provide technical support for the design of the enforcement of next step well stimulation of oil field and raising recovery ratio scheme.

Describe the present invention below in conjunction with the drawings and specific embodiments, but not as a limitation of the invention.

Accompanying drawing explanation

Fig. 1 is water controlled field advantage channel recognition method flow diagram of the present invention;

Fig. 2 is the well testing characteristic feature curve of reservoir while being normal reservoir (not having advantage passage in reservoir);

Fig. 3 is the well testing characteristic feature curve while there is common high permeability zone in reservoir;

Fig. 4 is the well testing characteristic feature curve while there is strong high infiltration strip in reservoir;

Fig. 5 A is the WELL TEST INTERPRETATION MODEL schematic diagram of macropore;

Fig. 5 B is the well testing characteristic feature curve while there is macropore in reservoir;

Fig. 6 is water controlled field advantage passage identification device block diagram of the present invention;

Fig. 7 is the transient well test test result of one embodiment of the invention;

Fig. 8 is the transient well test test result for the second time of one embodiment of the invention;

Fig. 9 is the transient well test test result of one embodiment of the invention.

Wherein, Reference numeral

1 arranges characteristic feature curve plate module

2 bottom hole pressure measurement modules

3 bottom pressure derivative calculations modules

4 data smoothing processing modules

5 draw well testing relation curve module

6 judge modules

M pressure derivative curve over time

N pressure curve over time

A～e, b0, a1～a3 step

The specific embodiment

Below in conjunction with accompanying drawing, structural principle of the present invention and operating principle are described in detail:

The invention discloses a kind of water controlled field advantage channel recognition method and device based on transient well test.Mainly, by oil well is carried out to pressure buildup test, utilize bottom pressure and the time dependent curve of derivative thereof of actual measurement, the advantage passage forming in water controlled field development process is identified.Advantage passage is identified to the problem that is mainly concerned with two broad aspect: (1) determines in reservoir, whether there is advantage passage; (2) degree that Diagnostic Superiority passage is grown.

The present invention is in order to solve the above-mentioned two large problems in advantage channel recognition process, overcome that conventional advantage channel recognition method is inaccurate, imperfection, be subject to subjective factor to affect large shortcoming, take transient well test test as basis, set up a kind of recognition technology for different stage advantage passage, provide technical support as the enforcement of next step well stimulation of oil field and the design of raising recovery ratio scheme.

Referring to Fig. 1, Fig. 1 is water controlled field advantage channel recognition method flow diagram of the present invention.The invention provides a kind of water drive advantage channel recognition method based on transient well test.It is mainly that application transient pressure recovery well test data is identified the advantage passage forming in water controlled field development process, by oil well is carried out to pressure buildup test, utilize the pressure and the differential of pressure curve that obtain to identify the advantage passage forming in water controlled field development process.Comprise the steps:

Well testing characteristic feature curve plate step a is set: the well testing characteristic feature curve plate that advantage channel recognition is set;

Well testing bottom hole pressure measurement step b: pressure gauge (the present embodiment is preferably high-precise electronic pressure manometer) is lowered to well testing test purpose layer middle part, and surface shut-in, utilizes pressure gauge to record the bottom pressure that well testing recovered with the testing time;

Well testing bottom pressure derivative calculations step c: the bottom pressure that calculates described well testing to the first derivative of time natural logrithm as bottom pressure derivative;

Draw actual measurement well testing relation curve steps d: take the testing time as abscissa, take flowing bottomhole pressure (FBHP) and pressure derivative as ordinate, in log-log coordinate system, draw described bottom pressure or the time dependent actual measurement well testing of described bottom pressure derivative relation curve; Described actual measurement well testing relation curve is the double-log relation curve of zero dimension bottom pressure and non dimensional time or the double-log relation curve of zero dimension bottom pressure derivative and non dimensional time.

The existence of judgement advantage passage and grow rank step e: the described well testing characteristic feature curve of described actual measurement well testing relation curve and advantage channel recognition is carried out to form comparison, judge whether advantage passage exists and determine its growth rank.

Before described drafting actual measurement well testing relation curve steps d, also comprise:

Data smoothing treatment step d0: described bottom pressure or described bottom pressure derivative and the relation of time are carried out to data smoothing processing to reduce noise.Wherein, described data smoothing treatment step can adopt Wavelet Transform, linear interpolation exponential smoothing or Fourier transform to carry out data smoothing processing to described bottom pressure or described bottom pressure derivative.Owing to existing many uncertain factors in transient well test process, in the bottom pressure signal that these uncertain factors can make high-grade pressure gauge record, sneak into interfering signal (noise).If do not adopt suitable algorithm to carry out noise reduction, can cause bottom pressure and differential of pressure curve to occur larger fluctuation, cause curvilinear characteristic not obvious, may affect the practical application effect of this invention.Therefore the present embodiment preferably adopts the small wave converting method in mathematics to carry out smooth treatment to the bottom pressure data of actual measurement, to reach the object of noise reduction.

The described well testing characteristic feature curve plate step that arranges comprises and normal reservoir well test curve plate is set and advantage passage well testing characteristic feature curve plate is set.Wherein, when reservoir is normal reservoir (not having advantage passage in reservoir), be regarded as Homogeneous Reservoir.The WELL TEST INTERPRETATION MODEL of such reservoir is the transient seepage flow model of center, the infinitely great stratum of traditional homogeneous a bite well, can adopt laplace conversion to carry out Analytical Solution or finite difference method is carried out numerical solution.The typie well-testing curve of such reservoir is conventional curve of the prior art, and concrete solution procedure and the typical curve of model are more ripe prior art, and therefore not to repeat here.In the present embodiment, described normal reservoir well test curve plate is the transient seepage flow model curve plate of center, the infinitely great stratum of homogeneous a bite well.Referring to Fig. 2, Fig. 2 is the well testing characteristic feature curve of reservoir while being normal reservoir (not having advantage passage in reservoir).Wherein, in accompanying drawing, M is pressure derivative curve over time, and N is pressure curve over time, and M in following figure, N implication are identical.Pressure and pressure derivative have fixing implication in well testing subject.

In the present embodiment, according to the origin cause of formation of advantage passage and growth rank, advantage passage is grown from weak to strong and is divided into three classes: common high permeability zone, strong high infiltration strip and macropore, take out typical physical model according to its seepage characteristics respectively, set up corresponding well test analysis Mathematical Modeling with this, and it is solved, draw the characteristic feature curve of different stage advantage channel recognition.

Wherein, the described advantage passage well testing characteristic feature curve plate that arranges specifically comprises:

Set up model condition step a1 is set: set up according to the origin cause of formation of advantage passage and growth rank the assumed condition that model arranges;

Set up Mathematical Modeling step a2: the assumed condition according to the origin cause of formation of described advantage passage and growth rank is set up respectively corresponding Mathematical Modeling;

Model solution and characteristic feature Drawing of Curve step a3: respectively described Mathematical Modeling solved and draw corresponding advantage passage well testing characteristic feature curve plate according to solving result.

Wherein, described advantage passage well testing characteristic feature curve plate grows from weak to strong and comprises common high permeability zone indicatrix plate, strong high infiltration strip indicatrix plate and macropore indicatrix plate according to the origin cause of formation of advantage passage and growth rank.

Illustrate the process of establishing of common high permeability zone indicatrix plate, strong high infiltration strip indicatrix plate and macropore indicatrix plate below.

Referring to Fig. 3, Fig. 3 is the well testing characteristic feature curve while there is common high permeability zone in reservoir.While there is common high permeability zone in reservoir, be regarded as stratified reservoir.

A1, model hypothesis condition are as follows:

1. oil well is to determine yield production;

2. formation fluid and rock are all micro-compressible, and compression coefficient is constant;

3. formation fluid is single-phase, and flowing in two seepage fields all meets Darcy's law;

4. consider the impact of well hole storage and skin effect;

5. in the front stratum of oil well test, each point pressure is identical, is p _i;

6. ignore the impact of gravity and capillary force, and in stratum, barometric gradient is less;

7. the degree of porosity of every kind of medium and the pressure of another kind of medium change separate;

8. between two-layer, be connected, and quasi-stable state channelling occurs between the two;

A2, set up Mathematical Modeling

Nondimensional number definition

In model, subscript 1 represents normal reservoir, and subscript 2 represents common high permeability zone.

1. zero dimension pressure:

$P_{\mathrm{Dj}}=\frac{k_1{h}_1+k_2{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">h</figure-callout>}}_2}{1.842\&times;{10}^{-3}\mathrm{q\&mu;B}}\mathrm{\&Delta;}{p}_j$

In formula: Δ p _j=p _i-p _j, j=1,2

2. non dimensional time:

$t_D=\frac{3.6(k_1{h}_1+k_2{h}_2)}{[{\left(\mathrm{\&phi;}{C}_{t}h\right)}_1+{\left(\mathrm{\&phi;}{C}_{t}h\right)}_2]\mathrm{\&mu;}{r}_w^2}t$

3. zero dimension well hole storage coefficient

$C_{D1}=\frac{\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">C</figure-callout>}}{2\mathrm{\&pi;}{\left(\mathrm{\&phi;}{C}_{t}h\right)}_1{\mathrm{<figure-callout\; id="2"\; label="r\; w"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">r</figure-callout>}}_w^{}},$ ${\mathrm{<figure-callout\; id="2"\; label="C\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">C</figure-callout>}}_D=\frac{\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">C</figure-callout>}}{2\mathrm{\&pi;}{\left(\mathrm{\&phi;}{C}_{t}h\right)}_2{\mathrm{<figure-callout\; id="2"\; label="r\; w"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">r</figure-callout>}}_w^{}}$

$C_D=\frac{\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">C</figure-callout>}}{2\mathrm{\&pi;}[{\left(\mathrm{\&phi;}{C}_{t}h\right)}_1+{\left(\mathrm{\&phi;}{C}_{t}h\right)}_2]{\mathrm{<figure-callout\; id="2"\; label="r\; w"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">r</figure-callout>}}_w^{}}$

4. stored energy ratio

$\mathrm{\&omega;}=\frac{{\left(\mathrm{\&phi;}{C}_{t}h\right)}_1}{{\left(\mathrm{\&phi;}{C}_{t}h\right)}_1+{\left(\mathrm{\&phi;}{C}_{t}h\right)}_2}$

5. interporosity flow coefficient

$\mathrm{\&lambda;}={\mathrm{\&alpha;r}}_w^2\frac{k_1{h}_1}{k_1{h}_1+k_2{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">h</figure-callout>}}_2}$

6. formation capacity ratio

$\mathrm{\&kappa;}=\frac{k_1{h}_1}{k_1{h}_1+k_2{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">h</figure-callout>}}_2}$

7. zero dimension radius

$r_D=\frac{r}{r_w}$

Mathematical Modeling

$\left\{\begin{array}{c}\mathrm{\&kappa;}\frac{1}{r_D}\frac{\&PartialD;}{\&PartialD;r_D}\left(r_D\frac{\&PartialD;P_{D1}}{\&PartialD;r_D}\right)-\mathrm{\&lambda;}(P_{D1}-P_{D2})=\mathrm{\&omega;}\frac{\&PartialD;P_{D1}}{\&PartialD;t_D}\\ (1-\mathrm{\&kappa;})\frac{1}{r_D}\frac{\&PartialD;}{\&PartialD;r_D}\left(r_D\frac{\&PartialD;{\mathrm{<figure-callout\; id="2"\; label="P\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">P</figure-callout>}}_D}{\&PartialD;r_D}\right)+\mathrm{\&lambda;}(P_{D1}-P_{D2})=(1-\mathrm{\&omega;})\frac{\&PartialD;{\mathrm{<figure-callout\; id="2"\; label="P\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">P</figure-callout>}}_D}{\&PartialD;t_D}\\ P_{D1}(r_D,0)=P_{D2}(r_D,0)=0\\ C_D\frac{{\mathrm{dP}}_{\mathrm{wD}}}{\mathrm{dt}}-\mathrm{\&kappa;}\frac{\&PartialD;P_{D1}}{\&PartialD;r_D}{|}_{r_D=1}-(1-\mathrm{\&kappa;})\frac{\&PartialD;{\mathrm{<figure-callout\; id="2"\; label="P\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">P</figure-callout>}}_D}{\&PartialD;r_D}{|}_{r_D=1}=1\\ P_{\mathrm{wD}}={[P_{D1}-S_1\left(r_D\frac{{\&PartialD;P}_{D1}}{\&PartialD;r_D}\right)]}_{r_D=1}{[P_{D2}-S_2\left(r_D\frac{\&PartialD;{\mathrm{<figure-callout\; id="2"\; label="P\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">P</figure-callout>}}_D}{\&PartialD;r_D}\right)]}_{r_D=1}\\ P_{D1}(r_{\mathrm{eD}},t_D)=P_{D2}(r_{\mathrm{eD}},t_D)=0\end{array}\right.$

A3, model solution

Adopting Douglas-Jones predictor-corrector method to realize herein solves the difference of this model.The result that utilization solves can be drawn the well testing typical curve (referring to Fig. 3) of common high permeability zone.

Referring to Fig. 4, Fig. 4 is the well testing characteristic feature curve while there is strong high infiltration strip in reservoir.While there is strong high infiltration strip in reservoir, be regarded as horizontal fracture.

Under the infinite reservoir condition of micro-compressible, the up-and-down boundary sealing of fluid, a continuous point source is positioned at (x _w, y _w, z _w) locate, observation point is positioned at (x, y, z) to be located, and Laplce's Space Solutions of the pressure distribution that point source produces is:

$\stackrel{\&OverBar;}{\mathrm{\&Delta;p}}=\frac{\tilde{q}\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">u</figure-callout>}}{2\mathrm{\&pi;kL}{h}_{D}s}[K_0\left(r_D\sqrt{u}\right)+2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{K}_0\left(r_D{\mathrm{\&epsiv;}}_n\right)\cos \mathrm{n\&pi;}\frac{z}{h}\cos \mathrm{n\&pi;}\frac{z_w}{h}]$

In formula ---Laplce's Space Solutions of Pressure difference distribution;

---the output of point source, cm ³/ s;

μ---liquid viscosity, mPas;

K---in-place permeability, μ m ²;

L---reference length, cm;

S---Laplce's space variable;

K ₀---the Bessel function of Equations of The Second Kind correction;

H---reservoir thickness, cm;

U---u=sf (s), wherein f (s) is the amount relevant with reservoir properties.In the time that oil reservoir is Homogeneous Reservoir, f (s)=1; In the time that oil reservoir is Double Porosity Reservoir, f (s) is the function of interporosity flow coefficient, elastic storativity ratio and Laplce's space variable.

Definition dimensionless variable is as follows:

$x_D=\frac{x}{L};$ $y_D=\frac{y}{L};$ $h_D=\frac{h}{L}\sqrt{\frac{k}{k_z}};$

${\mathrm{\&epsiv;}}_n=\sqrt{u+{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">n</figure-callout>}}^2{\mathrm{\&pi;}}^2/{\mathrm{<figure-callout\; id="2"\; label="h\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">h</figure-callout>}}_D^{}};$

${\mathrm{<figure-callout\; id="2"\; label="r\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">r</figure-callout>}}_D^{}={(x_D-x_{\mathrm{wD}})}^2+{(y_D-y_{\mathrm{wD}})}^2.$

According to principle of stacking, continuous point source solution is carried out to integration in the strong high infiltration strip plane of rectangle, the pressure-responsive formula that can obtain the strong high infiltration strip of uniform flux is

$\stackrel{\&OverBar;}{\mathrm{\&Delta;p}}={\&Integral;}_{X-L_f}^{X+L_f}{\&Integral;}_{Y-\frac{b}{2}}^{Y+\frac{b}{2}}\frac{\tilde{q}\mathrm{\&mu;}}{2\mathrm{\&pi;kL}{h}_{D}s}[K_0\left(r_D\sqrt{u}\right)+2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{K}_0\left(r_D{\mathrm{\&epsiv;}}_n\right)\cos \mathrm{n\&pi;}\frac{z}{h}\cos \mathrm{n\&pi;}\frac{z_w}{h}]d{y}_w{\mathrm{dx}}_w$

In formula (X, Y)---position in the plane, the well point of advantage passage well;

L _f---half length of advantage passage, cm;

B---the width of advantage passage, cm.

Definition $\widetilde{L_f}=\frac{L_f}{L},$ $\tilde{b}=\frac{b}{L},$ ?

$\stackrel{\&OverBar;}{\mathrm{\&Delta;p}}=\frac{\tilde{q}\mathrm{\&mu;}}{2\mathrm{\&pi;kL}{h}_{D}s}\left[{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">L</figure-callout>}}^2{\&Integral;}_{X-\widetilde{L_f}}^{X+\widetilde{L_f}}{\&Integral;}_{Y-0.5\tilde{b}}^{Y+0.5\tilde{b}}{K}_0(\sqrt{{(x_D-x_{\mathrm{wD}})}^2+{(y_D-y_{\mathrm{wD}})}^2}\&CenterDot;\sqrt{u}){\mathrm{dy}}_{\mathrm{wD}}{\mathrm{dx}}_{\mathrm{wD}}\right]$

$+\frac{\tilde{q}\mathrm{\&mu;}}{2\mathrm{\&pi;kL}{h}_{D}s}\left[2{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">L</figure-callout>}}^2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}\cos \mathrm{n\&pi;}\frac{z}{h}\cos \mathrm{n\&pi;}\frac{z_w}{h}{\&Integral;}_{X-\widetilde{L_f}}^{X+\widetilde{L_f}}{\&Integral;}_{Y-0.5\tilde{b}}^{Y+0.5\tilde{b}}{K}_0(\sqrt{{(x_D-x_{\mathrm{wD}})}^2+{(y_D-y_{\mathrm{wD}})}^2}\&CenterDot;{\mathrm{\&epsiv;}}_n)\right]{\mathrm{dy}}_{\mathrm{wD}}{\mathrm{dx}}_{\mathrm{wD}}$

Definition α, β is integration variable, represents respectively the poor of the nondimensional transverse and longitudinal coordinate in certain point source and well point, can obtain:

In x direction: x _wD-X _d=α

In y direction: y _wD-Y _d=β

:

x _D-x _wD＝x _D-(X _D+α)＝x _D-X _D-α

y _D-y _wD＝y _D-(Y _D+β)＝y _D-Y _D-β

Definition $\widetilde{x_D}=x_D-X_D-\mathrm{\&alpha;},$ $\widetilde{y_D}=y_D-Y_D-\mathrm{\&beta;},$ Can obtain

$\stackrel{\&OverBar;}{\mathrm{\&Delta;p}}=\frac{\tilde{q}\mathrm{\&mu;<figure-callout\; id="2"\; label="L"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">L</figure-callout>}}{2\mathrm{\&pi;k}{h}_{D}s}[{\&Integral;}_{-\mathrm{Lf}}^{\mathrm{Lf}}{\&Integral;}_{-0.5b}^{0.5b}{K}_0(\sqrt{{\widetilde{x_D}}^2+{\widetilde{y_D}}^2}\&CenterDot;\sqrt{u})\mathrm{d\&alpha;d\&beta;}+2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}\cos \mathrm{n\&pi;}\frac{z}{h}\cos \mathrm{n\&pi;}\frac{z_w}{h}\&times;$

${\&Integral;}_{-\mathrm{Lf}}^{\mathrm{Lf}}{\&Integral;}_{-0.5b}^{0.5b}{K}_0(\sqrt{{\widetilde{x_D}}^2+{\widetilde{y_D}}^2}\&CenterDot;{\mathrm{\&epsiv;}}_n)\mathrm{d\&alpha;d\&beta;}$

The coordinate of getting well point is (0,0, z _w), half length that reference length is strong high infiltration strip, utilize following relational expression to carry out zero dimension to it:

$q=\tilde{q}\&CenterDot;2\mathrm{Lfb}$

$\stackrel{\&OverBar;}{p_D}=\frac{2\mathrm{\&pi;kh}\stackrel{\&OverBar;}{\mathrm{\&Delta;p}}}{\mathrm{q\&mu;}}$

$\stackrel{\&OverBar;}{p_D}=\frac{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">h</figure-callout>}}{2\mathrm{bs}{h}_S}[{\&Integral;}_{-\widetilde{L_f}}^{\widetilde{L_f}}{\&Integral;}_{-0.5\tilde{b}}^{0.5\tilde{b}}{K}_0(\sqrt{{(x_D-\mathrm{\&alpha;})}^2+{(y_D-\mathrm{\&beta;})}^2}\&CenterDot;\sqrt{u})\mathrm{d\&alpha;d\&beta;}+$

$2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{n\&pi;}\frac{z_w}{h}{\&Integral;}_{-L_f}^{L_f}{\&Integral;}_{-0.5b}^{0.5b}{K}_0(\sqrt{{(x_D-\mathrm{\&alpha;})}^2+{(y_D-\mathrm{\&beta;})}^2}\&CenterDot;{\mathrm{\&epsiv;}}_n)\mathrm{d\&alpha;d\&beta;}]$

Definition $L_D=\frac{1}{h_D}=\frac{L_f}{h},$ $e=\frac{b}{L_f},$ Can obtain

$\stackrel{\&OverBar;}{p_D}=\frac{1}{2\mathrm{se}}[{\&Integral;}_{-1}^1{\&Integral;}_{-0.5e}^{0.5e}{K}_0(\sqrt{{(x_D-\mathrm{\&alpha;})}^2+{(y_D-\mathrm{\&beta;})}^2}\&CenterDot;\sqrt{u})\mathrm{d\&alpha;d\&beta;}+$

$2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{n\&pi;}\frac{z_w}{h}{\&Integral;}_{-1}^1{\&Integral;}_{-0.5e}^{0.5e}{K}_0(\sqrt{{(x_D-\mathrm{\&alpha;})}^2+{(y_D-\mathrm{\&beta;})}^2}\&CenterDot;{\mathrm{\&epsiv;}}_n)\mathrm{d\&alpha;d\&beta;}]$

Laplce's Space Solutions of bottom hole pressure difference is:

$\stackrel{\&OverBar;}{p_D}=\frac{1}{2\mathrm{se}}[{\&Integral;}_{-1}^1{\&Integral;}_{-0.5e}^{0.5e}{K}_0(\sqrt{{\mathrm{\&alpha;}}^2+{\mathrm{\&beta;}}^2}\&CenterDot;\sqrt{u})\mathrm{d\&alpha;d\&beta;}+$

$2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{n\&pi;}\frac{z_w}{h}{\&Integral;}_{-1}^1{\&Integral;}_{-0.5e}^{0.5e}{K}_0(\sqrt{{\mathrm{\&alpha;}}^2+{\mathrm{\&beta;}}^2}\&CenterDot;{\mathrm{\&epsiv;}}_n)\mathrm{d\&alpha;d\&beta;}]$

In formula ${\mathrm{\&epsiv;}}_n-$ ${\mathrm{\&epsiv;}}_n=\sqrt{u+{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">n</figure-callout>}}^2{\mathrm{\&pi;}}^2{\mathrm{<figure-callout\; id="2"\; label="L\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">L</figure-callout>}}_D^{}};$

U---u=sf (s), f in Homogeneous Reservoir (s)=1, f in Double Porosity Reservoir (s) is the function of elastic storativity ratio, interporosity flow coefficient.

Further utilize Laplce's flow convolution relation, consider well hole storage coefficient C _dduring with the affecting of skin factor S, Laplce's Space Solutions of strong high infiltration strip model is:

$\stackrel{\&OverBar;}{p_{\mathrm{wD}}}=\frac{s\stackrel{\&OverBar;}{p_D}+S}{s+C_D{s}^2(s\stackrel{\&OverBar;}{p_D}+S)}$

Employing Stehfest the Method for Numerical Inversion can be by the inverting of Laplce's Space Solutions in real space.Then utilize solving result can draw the well testing typical curve (referring to Fig. 4) of strong high infiltration strip.

Referring to Fig. 5 A and Fig. 5 B, the WELL TEST INTERPRETATION MODEL schematic diagram that Fig. 5 A is macropore, Fig. 5 B is the well testing characteristic feature curve while there is macropore in reservoir.While there is macropore in reservoir, it flows for one dimension non-darcy flow.

This part is the mobile one dimension non-darcy flow that is considered as of fluid in macropore, set up and the Coupled Flow model of flow through oil reservoir, and adopted and resolve numerical value mixed method this model is solved.Model schematic diagram as shown in Figure 5A.

A1, assumed condition

1. single-phase, isothermal, micro-compressible fluid, system compressibility is C, fluid viscosity is μ;

2. Reservoir anisotropy, horizontal direction permeability is k, vertical direction permeability is k _z;

3. top bottom interface sealing, i.e. z=0, z=h place is impermeable;

4. external boundary is infinitely great;

5. because the volume of macropore is very little, suppose the non-darcy flow for one dimension in macropore;

6. the output q of x=0 place is definite value, and x=L place flow is 0, and fluid only flows in well by the wall of macropore;

7. different time diverse location place flows into the flow difference in well by oil reservoir, in unit interval unit length, is q by the amount of fluid in oil reservoir inflow macropore _h(x, t), the flow in position x place macropore is:

$q_d(x,t)={\&Integral;}_x^L{q}_h(x^{\&prime;},t)d{x}^{\&prime;}.$

A2, set up Mathematical Modeling

Zero dimension

1. zero dimension pressure:

$p_D=\frac{\mathrm{kh}(p_i-p)}{1.842\&times;{10}^{-3}\mathrm{q\&mu;}}$

2. non dimensional time:

$t_D=\frac{3.6\mathrm{kt}}{\mathrm{\&phi;\&mu;}{C}_t\&CenterDot;{(L/2)}^2}$

3. dimensionless coordinate:

$x_D=\frac{x}{L/2},$ $y_D=\frac{y}{L/2},$ $z_{\mathrm{wD}}=\frac{z_w}{h},$ $L_D=\frac{L}{2h}\sqrt{\frac{k_v}{k}}$

4. the zero dimension radius of macropore:

$r_{\mathrm{wD}}=\frac{r_{\mathrm{we}}}{h}=\frac{r_w}{2h}[{\left(\frac{k}{k_v}\right)}^{\frac{1}{4}}+{\left(\frac{k_v}{k}\right)}^{\frac{1}{4}}]$

In formula: r _wefor the equivalent redius of macropore in anisotropic reservoir;

5. nondimensional mass flow is:

$q_{\mathrm{dD}}=\frac{q_d}{q};$ $q_{\mathrm{hD}}=\frac{q_{h}L}{q}$

6. the zero dimension flow conductivity of macropore is:

$C_{\mathrm{dD}}=\frac{k_f{\mathrm{\&pi;<figure-callout\; id="2"\; label="r\; w"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">r</figure-callout>}}_w^{}}{\mathrm{kh}(L/2)}$

7. nondimensional mass flow constant is:

${\left(q_{\mathrm{DND}}\right)}_d=\frac{{10}^{-3}}{86400}\&CenterDot;\frac{k_f\mathrm{\&rho;\&beta;q}}{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="r\; w"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">r</figure-callout>}}_w^{}\mathrm{\&mu;}}$

Mathematical Modeling

1. the non-Darcy flow model in macropore

$p_{\mathrm{wD}}-p_{\mathrm{dDj}}=\frac{2\mathrm{\&pi;}}{C_{\mathrm{dD}}}{\&Integral;}_0^{x_{\mathrm{Dj}}}{q}_{\mathrm{dD}}{\mathrm{dx}}_D^{\&prime;}+\frac{2\mathrm{\&pi;}}{C_{\mathrm{dD}}}{\left(q_{\mathrm{DND}}\right)}_d{\&Integral;}_0^{x_{\mathrm{<figure-callout\; id="2"\; label="Dj\; q\; dD"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">Dj</figure-callout>}}}{q}_{\mathrm{dD}}^{}{}_2^{}{\mathrm{dx}}_D^{\&prime;}$

Above formula is carried out to difference discrete:

${\&Integral;}_0^{x_{\mathrm{Dj}}}{q}_{\mathrm{dD}}{\mathrm{dx}}_D^{\&prime;}=\underset{i=1}{\overset{j-1}{\mathrm{\&Sigma;}}}(\frac{\mathrm{\&Delta;x}}{2}{q}_{\mathrm{dDi}}+\frac{\mathrm{\&Delta;x}}{2}{q}_{\mathrm{dDi}+1})+\frac{3}{8}\mathrm{\&Delta;x}\&CenterDot;q_{\mathrm{dDj}}+\frac{1}{8}\mathrm{\&Delta;x}\&CenterDot;q_{\mathrm{dDj}+1}$

${\&Integral;}_0^{x_{\mathrm{<figure-callout\; id="2"\; label="Dj\; q\; dD"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">Dj</figure-callout>}}}{q}_{\mathrm{dD}}^{}{}_2^{}{\mathrm{dx}}_D^{\&prime;}=\underset{i=1}{\overset{j-1}{\mathrm{\&Sigma;}}}(\frac{\mathrm{\&Delta;x}}{3}{\mathrm{<figure-callout\; id="2"\; label="q\; dDi"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{dDi}}^{}+\frac{\mathrm{\&Delta;x}}{3}{q}_{\mathrm{dDi}}{q}_{\mathrm{dDi}+1}+\frac{\mathrm{\&Delta;x}}{3}{q}_{\mathrm{dDi}+1}^2)+\frac{7}{24}\mathrm{\&Delta;<figure-callout\; id="2"\; label="x\; q\; dDj"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">x</figure-callout>}{q}_{\mathrm{dDj}}^{}{}_2^{}+\frac{1}{6}\mathrm{\&Delta;x}{q}_{\mathrm{dDj}}{\&CenterDot;q}_{\mathrm{dDj}+1}+\frac{1}{24}{\mathrm{\&Delta;xq}}_{\mathrm{dDj}+1}^2$

2. reservoir model

$p_{\mathrm{dD}}(x_{\mathrm{Dj}},r_{\mathrm{wD}},t_D)=\widehat{p_{\mathrm{dD}}}(x_{\mathrm{Dj}},r_{\mathrm{wD}},t_{\mathrm{DN}})+\underset{i=1}{\overset{M}{\mathrm{\&Sigma;}}}\frac{2(q_{\mathrm{dDi}}-q_{\mathrm{dDi}+1})}{\mathrm{\&Delta;x}}{\&Integral;}_0^{t_{\mathrm{DN}}-t_{\mathrm{DN}-1}}{S}_i(x_{\mathrm{Dj}},t_D^{\&prime;})d{t}_D^{\&prime;}$

In formula:

$\widehat{p_{\mathrm{dD}}}(x_{\mathrm{Dj}},r_{\mathrm{wD}},t_{\mathrm{DN}})=\underset{k=1}{\overset{N-1}{\mathrm{\&Sigma;}}}\underset{i=1}{\overset{M}{\mathrm{\&Sigma;}}}{q}_{\mathrm{hDi}}\left(t_{\mathrm{Dk}}\right)[{\&Integral;}_0^{t_{\mathrm{DN}}-t_{\mathrm{Dn}-1}}{S}_i(x_{\mathrm{Dj}},t_D^{\&prime;}){\mathrm{dt}}_D^{\&prime;}-{\&Integral;}_0^{t_{\mathrm{DN}}-t_{\mathrm{Dn}}}{S}_i(x_{\mathrm{Dj}},t_D^{\&prime;})d{t}_D^{\&prime;}]$

$S_i(x_D,\mathrm{\&tau;})=\frac{\sqrt{\mathrm{\&pi;}}}{4}[\mathrm{erf}\left(\frac{x_D-\frac{2i-2}{\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">M</figure-callout>}}}{2\sqrt{\mathrm{\&tau;}}}\right)-\mathrm{erf}\left(\frac{x_D-\frac{2i}{M}}{2\sqrt{\mathrm{\&tau;}}}\right)]$

$\{1+2\underset{n=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}\exp [-{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">n</figure-callout>}}^2{\mathrm{\&pi;}}^2{\mathrm{<figure-callout\; id="2"\; label="L\; D"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">L</figure-callout>}}_D^{}\mathrm{\&tau;}\left]\cos \right[\mathrm{n\&pi;}(z_{\mathrm{wD}}+r_{\mathrm{wD}})\left]\cos \left({\mathrm{n\&pi;z}}_{\mathrm{wD}}\right)\right\}$

A3, model solution

The darcy flow model of the non-darcy flow model in macropore and oil reservoir is coupled, can obtains:

$p_{\mathrm{wD}}-\widehat{p_{\mathrm{dD}}}(x_{\mathrm{Dj}},r_{\mathrm{wD}},t_{\mathrm{DN}})-\underset{i=1}{\overset{M}{\mathrm{\&Sigma;}}}\frac{2(q_{\mathrm{dDi}}-q_{\mathrm{dDi}+1})}{\mathrm{\&Delta;x}}{\&Integral;}_0^{t_{\mathrm{DN}}-t_{\mathrm{DN}-1}}{S}_i(x_{\mathrm{Dj}},t_D^{\&prime;}){\mathrm{dt}}_D^{\&prime;}$

$=\frac{2\mathrm{\&pi;}}{C_{\mathrm{dD}}}[\underset{i=1}{\overset{j-1}{\mathrm{\&Sigma;}}}(\frac{\mathrm{\&Delta;x}}{2}{q}_{\mathrm{dDi}}+\frac{\mathrm{\&Delta;x}}{2}{q}_{\mathrm{dDi}+1})+\frac{3}{8}\mathrm{\&Delta;x}\&CenterDot;q_{\mathrm{dDj}}+\frac{1}{8}\mathrm{\&Delta;x}\&CenterDot;q_{\mathrm{dDj}+1}]+$

$\frac{2\mathrm{\&pi;}}{C_{\mathrm{dD}}}{\left(q_{\mathrm{DND}}\right)}_d\left[\begin{array}{c}\underset{i=1}{\overset{j-1}{\mathrm{\&Sigma;}}}(\frac{\mathrm{\&Delta;x}}{3}{\mathrm{<figure-callout\; id="2"\; label="q\; dDi"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">q</figure-callout>}}_{\mathrm{dDi}}^{}+\frac{\mathrm{\&Delta;x}}{3}{q}_{\mathrm{dDi}}{q}_{\mathrm{dDi}+1}+\frac{\mathrm{\&Delta;x}}{3}{q}_{\mathrm{dDi}+1}^2)\\ +\frac{7}{24}\mathrm{\&Delta;<figure-callout\; id="2"\; label="x\; q\; dDj"\; filenames="HDA0000085061060000041.png"\; state="\{\{state\}\}">x</figure-callout>}{q}_{\mathrm{dDj}}^{}{}_2^{}+\frac{1}{6}\mathrm{\&Delta;x}{q}_{\mathrm{dDj}}\&CenterDot;q_{\mathrm{dDj}+1}+\frac{1}{24}\mathrm{\&Delta;x}{q}_{\mathrm{dDj}+1}^2\end{array}\right]$

Macropore is divided into M section, has q _dDi(i=1,2 ..., M+1).Therefore in above formula, have M+2 unknown number: p altogether _wD, q _dDi(i=1,2 ..., M+1).

The formula above formula of utilization can be listed as M equation, adds two fringe conditionss:

q _dD(1)＝q，q _dD(M)＝0

Therefore above formula can solve.But it is nonlinear equation, therefore adopt Newton-Raphson alternative manner to solve.Utilize solving result can draw the well testing typical curve of macropore (referring to Fig. 5 B).

Referring to Fig. 6, Fig. 6 is water controlled field advantage passage identification device block diagram of the present invention.Water controlled field advantage passage identification device of the present invention, application transient pressure recovers well test data to be identified the advantage passage forming in water controlled field development process, comprising:

Characteristic feature curve plate module 1 is set: for arranging and store the well testing characteristic feature curve plate of advantage channel recognition;

Bottom hole pressure measurement module 2: comprise pressure gauge and pressure record unit, described pressure gauge is conveyed into described pressure record unit for testing well testing with the bottom pressure of testing time recovery the described bottom pressure that test is obtained;

Bottom pressure derivative calculations module 3: for calculate described bottom pressure to the first derivative of time natural logrithm as bottom pressure derivative and store this bottom pressure derivative;

Draw well testing relation curve module 5: for drawing described bottom pressure or the time dependent actual measurement well testing of described bottom pressure derivative relation curve in log-log coordinate system;

Judge module 6: for the described well testing characteristic feature curve of described actual measurement well testing relation curve and advantage channel recognition is carried out to form comparison, judge advantage passage whether exist and determine its grow rank.

Also can comprise:

Data smoothing processing module 4: for described bottom pressure or described bottom pressure derivative and the relation of time are carried out data smoothing process after the described drafting actual measurement of input well testing relation curve module.

Above-mentioned modules can be arranged in computer, and the control by setting computer to each module can realize automatic detection and judgement.Can utilize the demonstration output module of computer and show output equipment (such as display screen, printer etc.), by detection and judgment result displays or output simultaneously.Also drawn characteristic feature curve plate can be stored in the store-memory module of computer in advance, directly perform step b～step e.The circulation of this step in computer carried out and judged whether advantage passage exists and determine that its idiographic flow of growing rank all can adopt more ripe prior art, and therefore not to repeat here.

Below take concrete three test results as example Benq in the practical situations of the advantage channel recognition method of transient well test.

Embodiment mono-

Selected well testing oilfield reservoir physical property is good, is high hole middle and high infiltration reservoir, rock loose cementation, and chink content is less.Through exploitation for many years, enter at present high water-cut stage, in block, advantage passage is grown seriously, causes oil-well drainage remaining oil saturation high, and well draining is flooded seriously, and longitudinally intake profile is widely different, and waterline tempo of penetration is very fast.The existence of advantage passage has caused serious impact to the further raising of this oil recovery rate.

The practical situations of the advantage channel recognition method of explanation based on transient well test as an example of this oil field A well example below.In advance this oil field A well has been carried out respectively to twice transient well test test, this twice testing time was separated by more than 1 year.Twice test process all carries out according to " SY/T6172-2006 People's Republic of China (PRC) oil and gas industry standard---oil well Well Test Technology standard ", and record the flowing bottomhole pressure (FBHP) in test process, calculating pressure derivative is drawn flowing bottomhole pressure (FBHP) and the time dependent test curve of pressure derivative thereof of actual measurement under log-log coordinate system.The test curve that twice of front and back test result is drawn is respectively as shown in accompanying drawing 7, Fig. 8.

This oil field A well is tested for the first time to the well testing characteristic feature curve of obtained flowing bottomhole pressure (FBHP) and the time dependent curve of pressure derivative (seeing accompanying drawing 7) and different stage advantage passage provided by the invention and (seen accompanying drawing 2, accompanying drawing 3, accompanying drawing 4 and accompanying drawing 5A) compare, can find in accompanying drawing 7 that in test curve and Fig. 3, the trend of characteristic feature curve is in full accord, and differ greatly with other characteristic feature curve, therefore can judge A well and have advantage passage around in the time testing for the first time, but the growth rank of advantage passage is lower, can be classified as common high permeability zone.

According to same step, the time dependent curve of the flowing bottomhole pressure (FBHP) that A well is recorded for the second time and pressure derivative thereof (seeing accompanying drawing 8) is analyzed.In test curve in discovery accompanying drawing 8 and Fig. 4, the trend of characteristic feature curve is in full accord, and differ greatly with other characteristic feature curve, therefore can judge A well and still have advantage passage around in the time testing for the second time, and the growth rank of advantage passage improves, can be classified as strong high infiltration strip.

This well has all carried out Interwell tracer monitoring after twice transient well test test.Tracer monitoring explanation results is also in full accord with the explanation results of transient well test method.

Embodiment bis-

The practical situations of the advantage channel recognition method based on transient well test is described as an example of test oil field B well example.Flowing bottomhole pressure (FBHP) and the time dependent curve of pressure derivative (seeing accompanying drawing 9) thereof that B well surveying is tried to obtain compare with the well testing characteristic feature curve (seeing accompanying drawing 2, accompanying drawing 3, accompanying drawing 4 and accompanying drawing 5A) of different stage advantage passage provided by the invention, the trend that can find characteristic feature curve in test curve in accompanying drawing 9 and Fig. 5 is in full accord, and differ greatly with other characteristic feature curve, therefore can judge B well and have the very high advantage passage of growth rank around in when test, can be classified as macropore.

The explanation results of this well and the understanding of Oil Field are in full accord, and after this well is carried out to transient well test, well corresponding to this well are injected to gel particle and carry out profile control.Well when blocking agent is injected dynamically shows that B well exists macropore around, conforms to the recognition result of transient well test method.

The present invention, by oil well is carried out to pressure buildup test, records the data that in test process, bottom pressure recovers in time, calculates bottom pressure derivative; In log-log coordinate system, draw the zero dimension bottom pressure of actual measurement and the relation curve that derivative changes with non dimensional time thereof; The well testing typical curve of the different stage advantage passage providing in measured curve and the present invention is compared, can detect and judge this well around whether exist advantage passage with and grow rank, the method has the features such as accuracy is high, workable, and the enforcement that can be oilfield stimulation measure provides guidance.

Certainly; the present invention also can have other various embodiments; in the situation that not deviating from spirit of the present invention and essence thereof; those of ordinary skill in the art are when making according to the present invention various corresponding changes and distortion, but these corresponding changes and distortion all should belong to the protection domain of the appended claim of the present invention.

Claims (10)

1. a water controlled field advantage channel recognition method, is characterized in that, application transient pressure recovers well test data to be identified the advantage passage forming in water controlled field development process, comprises the steps:

A, well testing characteristic feature curve plate step is set: the well testing characteristic feature curve plate that advantage channel recognition is set;

B, well testing bottom hole pressure measurement step: pressure gauge is lowered to well testing test purpose layer middle part, and surface shut-in, utilizes pressure gauge to record the data that bottom pressure recovered with the testing time;

C, well testing bottom pressure derivative calculations step: the bottom pressure that calculates described well testing to the first derivative of time natural logrithm as bottom pressure derivative;

D, actual measurement well testing relation curve plot step: take the testing time as abscissa, take flowing bottomhole pressure (FBHP) and pressure derivative as ordinate, in log-log coordinate system, draw described bottom pressure or the time dependent actual measurement well testing of described bottom pressure derivative relation curve;

E, judge the existence of advantage passage and grow rank step: the described well testing characteristic feature curve of described actual measurement well testing relation curve and advantage channel recognition is carried out to form comparison, judge whether advantage passage exists and determine its growth rank.

2. water controlled field advantage channel recognition method as claimed in claim 1, is characterized in that, before described actual measurement well testing relation curve plot step, also comprises:

D0, data smoothing treatment step: described bottom pressure or described bottom pressure derivative and the relation of time are carried out to data smoothing processing to reduce noise.

3. water controlled field advantage channel recognition method as claimed in claim 2, it is characterized in that, described data smoothing treatment step adopts Wavelet Transform, linear interpolation exponential smoothing or Fourier transform to carry out data smoothing processing to described bottom pressure or described bottom pressure derivative.

4. the water controlled field advantage channel recognition method as described in claim 1,2 or 3, it is characterized in that, described actual measurement well testing relation curve is the double-log relation curve of zero dimension bottom pressure and non dimensional time or the double-log relation curve of zero dimension bottom pressure derivative and non dimensional time.

5. the water controlled field advantage channel recognition method as described in claim 1,2 or 3, it is characterized in that, the described well testing characteristic feature curve plate step that arranges comprises and normal reservoir well test curve plate is set and advantage passage well testing characteristic feature curve plate is set.

6. water controlled field advantage channel recognition method as claimed in claim 5, is characterized in that, described normal reservoir well test curve plate is the transient seepage flow model curve plate of center, the infinitely great stratum of homogeneous a bite well.

7. water controlled field advantage channel recognition method as claimed in claim 5, is characterized in that, the described advantage passage well testing characteristic feature curve plate that arranges comprises:

A1, set up model condition is set: according to the origin cause of formation of advantage passage and grow rank and set up the assumed condition that model arranges;

A2, set up Mathematical Modeling: set up respectively corresponding Mathematical Modeling according to the origin cause of formation of described advantage passage and the assumed condition of growing rank;

A3, model solution and characteristic feature Drawing of Curve: respectively described Mathematical Modeling solved and draw corresponding advantage passage well testing characteristic feature curve plate according to solving result.

8. water controlled field advantage channel recognition method as claimed in claim 7, it is characterized in that, described advantage passage well testing characteristic feature curve plate grows from weak to strong and comprises common high permeability zone indicatrix plate, strong high infiltration strip indicatrix plate and macropore indicatrix plate according to the origin cause of formation of advantage passage and growth rank.

9. a water controlled field advantage passage identification device, is characterized in that, application transient pressure recovers well test data to be identified the advantage passage forming in water controlled field development process, comprising:

Characteristic feature curve plate module is set: for arranging and store the well testing characteristic feature curve plate of advantage channel recognition;

Bottom hole pressure measurement module: comprise pressure gauge and pressure record unit, described pressure gauge is conveyed into described pressure record unit for testing well testing with the bottom pressure of testing time recovery the described bottom pressure that test is obtained;

Bottom pressure derivative calculations module: for calculate described bottom pressure to the first derivative of time natural logrithm as bottom pressure derivative and store this bottom pressure derivative;

Draw well testing relation curve module: for drawing described bottom pressure or the time dependent actual measurement well testing of described bottom pressure derivative relation curve in log-log coordinate system;

Judge module: for the described well testing characteristic feature curve of described actual measurement well testing relation curve and advantage channel recognition is carried out to form comparison, judge advantage passage whether exist and determine its grow rank.

10. water controlled field advantage passage identification device as claimed in claim 9, is characterized in that, also comprises:

Data smoothing processing module: for described bottom pressure or described bottom pressure derivative and the relation of time are carried out data smoothing process after the described drafting actual measurement of input well testing relation curve module.

Images