Disclosure of Invention
The invention aims to provide a research method for contribution of different acting forces to recovery ratio in an oil reservoir injection-production coupling mode, which solves the problem of quantitative description of the different acting forces in the injection-production coupling process.
The object of the invention can be achieved by the following technical measures: the method for researching the contribution of different acting forces to the recovery ratio in the oil reservoir injection-production coupling mode comprises the step 1 of establishing a model considering elasticity, gravity and capillary force and recording the model A, and recording the recovery ratio under the joint influence of the three acting forces as RElastic force + gravity + capillary force(ii) a Step 2, establishing a model considering the elastic force and the capillary force, recording the model as a model B, and recording the recovery ratio under the common influence of the two acting forces as a model RElastic force + capillary force(ii) a In the step 3, the step of,establishing a model considering elasticity and gravity, recording the model as model C, and recording the recovery ratio under the common influence of the two acting forces as RElastic force + gravity(ii) a Step 4, comparing the model A, B and the model A, C in pairs to obtain the contribution values R of different acting forces to the recovery ratioGravity force、RCapillary forceAnd R elastic force.
The object of the invention can also be achieved by the following technical measures:
in the step 1, rock compression coefficient, stratum structure data and a capillary force curve are respectively set, an oil reservoir numerical model considering elastic force, gravity and capillary force is established and recorded as a model A, and recovery ratio under the common influence of three acting forces is recorded as RElastic force + gravity + capillary force。
In step 1, the numerical reservoir model is established in two ways: the geological modeling is imported and established by using numerical simulation software, and the main parameters of model establishment input are as follows: the method comprises the following steps of constructing height, effective thickness of a reservoir, permeability, porosity, rock compression coefficient, fluid PVT parameters, rock property parameters including relative permeability curve and capillary pressure curve, and initialization parameters including reference depth, reference pressure and production system parameters of an injection and production well.
In step 1, the elastic force is influenced by the compression coefficient of rock, the capillary force is influenced by the capillary pressure curve, and the gravity is influenced by the reservoir formation and fault dip angle data.
In the step 1, the elastic force refers to the acting force of rock pores, fluid compression expansion energy and external energy supplement, and the rock compression coefficient is set according to block test data in the oil reservoir numerical simulation software to consider the influence of the elastic force; the influence of gravity on the recovery ratio is controlled by the oil reservoir structure, and the influence of the gravity on the recovery ratio is simulated by introducing a structure model; capillary force data are obtained by mercury intrusion experiments, and rock fluid part input water saturation S of numerical simulation softwarewForce of capillary PcowThe relationship of (a) simulates the effect of capillary force on recovery.
In step 2, modifying the construction parameters of the numerical reservoir model on the basis of the model A, setting the construction parameters as constant values, ensuring that each point of the reservoir is in the same horizontal plane, eliminating the influence of gravity, and establishing the considered bombThe numerical model of the oil reservoir of the sexual force and the capillary force is recorded as a model B, and the recovery ratio under the joint influence of the two acting forces is recorded as RElastic force + capillary force。
In step 3, deleting the capillary force experiment curve data on the basis of the model A, eliminating the influence of the capillary force, establishing an oil reservoir numerical model considering the elastic force and the gravity, recording the oil reservoir numerical model as a model C, and recording the recovery ratio under the common influence of the two acting forces as RElastic force + gravity。
In step 4, with RGravity forceRepresenting the effect of gravity on recovery, the effect of gravity on recovery is obtained by comparing model A with model B, RGravity forceModel a-model B | ═ RElastic force + gravity + capillary force-R elastic force+Capillary force.
In step 4, with RCapillary forceRepresenting the effect of capillary forces on recovery, obtained by comparing model A with model C, RCapillary forceModel a-model C | ═ RElastic force + gravity + capillary force-R elastic force+Gravity.
In step 4, with RElastic forceRepresenting the effect of elastic force on recovery, RElastic force=RElastic force + gravity + capillary force-RGravity force-RCapillary force。
According to the method for researching the contribution of different acting forces to the recovery ratio in the oil reservoir injection-production coupling mode, the method for researching the contribution of the elastic force, the gravity and the tubular force to the recovery ratio in the injection-production coupling process by using the oil reservoir numerical simulation software (CMG, Eclipse) can avoid the restriction of experimental conditions and experimenters, eliminate the influence of experimental errors, and can rapidly and repeatedly carry out quantitative characterization on the contribution of different acting forces to the recovery ratio in different production stages, so that the experimental cost and the time cost are saved.
Detailed Description
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
In the process of oil reservoir development, formation fluids (oil, gas and water) are influenced by three acting forces, namely elastic force, capillary force and gravity, the three acting forces can be respectively obtained by an indoor experimental method, but a research method for quantitative characterization is not formed in the aspect of contribution values of all acting forces to recovery ratio under the common influence of the three acting forces. On the basis, the invention provides a method for researching the contribution of elastic force, gravity and tube force to the recovery ratio in the injection-production coupling process by using numerical simulation software (CMG, Eclipse), and quantitatively represents the contribution of different acting forces to the recovery ratio.
As shown in fig. 1, fig. 1 is a flow chart of a method for researching the contribution of different acting forces to the recovery ratio in the injection-production coupling mode of a reservoir.
101, establishing a model considering elastic force, gravity and capillary force, recording the model as A, and recording the recovery ratio under the common influence of the three acting forces as RElastic force + gravity + capillary force;
Respectively setting rock compression coefficient, stratum structure data and a capillary force curve, establishing an oil reservoir numerical model considering elastic force, gravity and capillary force, recording the oil reservoir numerical model as a model A, and recording the recovery ratio under the common influence of the three acting forces as RElastic force + gravity + woolPipe force;
102, establishing a model considering elastic force and capillary force, recording the model as a model B, and recording the recovery ratio under the common influence of the two acting forces as a model RElastic force + capillary force;
Modifying the construction parameters of the numerical reservoir model on the basis of the model A, setting the construction parameters as constant values, ensuring that each point of the reservoir is positioned at the same horizontal plane, eliminating the influence of gravity, establishing the numerical reservoir model considering the elastic force and the capillary force, and recording the numerical reservoir model as a model B, and recording the recovery ratio under the joint influence of the two acting forces as a model RElastic force + capillary force;
103, establishing a model considering elasticity and gravity, and recording the model as a model C, and recording the recovery ratio under the common influence of the two acting forces as a model RElastic force + gravity;
Deleting the curve data of the capillary force experiment on the basis of the model A, eliminating the influence of the capillary force, establishing an oil reservoir numerical model considering the elastic force and the gravity, recording the oil reservoir numerical model as a model C, and recording the recovery ratio under the common influence of the two acting forces as RElastic force + gravity;
104, comparing the model A, B and the model A, C in pairs to obtain the contribution values R of different acting forces to the recovery ratioGravity force、RCapillary force、RElastic force。
With RGravity forceRepresenting the effect of gravity on recovery, the effect of gravity on recovery can be obtained by comparing model A with model B, RGravity forceModel a-model B | ═ RElastic force + gravity + capillary force-RElastic force + capillary force;
With RCapillary forceRepresenting the effect of capillary forces on recovery, which can be obtained by comparing model A with model C, RCapillary forceModel a-model C | ═ RElastic force + gravity + capillary force-RElastic force + gravity;
With RElastic forceRepresenting the effect of elastic force on recovery, RElastic force=RElastic force + gravity + capillary force-RGravity force-RHair with bristlesTube force.
The method determines the contribution of three acting forces to the recovery ratio aiming at the fault block oil reservoir developed by adopting the injection-production coupling mode, improves the micro understanding of the seepage rule in the injection-production coupling mode of the fault block oil reservoir, and is beneficial to greatly improving the utilization degree of the residual oil. The method can simulate and quantify the contribution of different production stages and different acting forces to the recovery ratio in real time, form a quantitative characterization method of the mechanical characteristics of injection-production coupling residual oil utilization, clarify the mechanical action mechanism of injection-production coupling, and save the experiment cost and the time cost.
Taking an injection-production coupling model with only one water injection well and one oil production well (abbreviated as injection-production) in a fault block oil reservoir as an example, assuming that the water content of the oil well is 50% and the injection-production ratio is 1 when the injection-production coupling is carried out, and the time for simulating the injection-production coupling development is 10 years, the method comprises the following steps (see fig. 1):
firstly, a model (see fig. 2) considering elastic force, gravity and capillary force is established and recorded as a model A, and the recovery ratio under the common influence of the three acting forces is recorded as RElastic force + gravity + capillary force。
The numerical reservoir model is established in two ways: geological modeling import and build using numerical simulation software. The main parameters of the model building input are: formation height, reservoir effective thickness, permeability, porosity, rock compressibility, fluid PVT parameters, rock property parameters (relative permeability curve and capillary pressure curve), initialization parameters (reference depth, reference pressure), injection and production regime parameters, etc.
The elastic force is influenced by the rock compression coefficient (measured by a rock compression coefficient instrument experiment), the capillary force is influenced by a capillary pressure curve (obtained by a mercury intrusion experiment), and the gravity is influenced by the oil reservoir stratum structure and fault dip angle data.
The elastic force of the formation fluid mainly refers to acting force supplemented by rock pores, fluid compression expansion energy and external energy, and the influence of the elastic force is considered by setting rock compression coefficients according to block test data in reservoir numerical simulation software (CMG, Eclipse).
The influence of gravity on the recovery ratio is mainly controlled by the oil reservoir structure, and the influence of gravity on the recovery ratio can be simulated by leading in a structure model.
Capillary force data are mainly obtained by mercury intrusion experiments, and the rock fluid part input water saturation S of numerical simulation softwarewForce of capillary PcowThe relationship of (a) can simulate the effect of capillary force on recovery.
Running the model, wherein the oil reservoir recovery ratio is influenced by three acting forces of elastic force, gravity and capillary force and is recorded as RElastic force + gravity + capillary force,RElastic force + gravity + capillary forceThe time dependence is shown in FIG. 3.
Secondly, modifying the construction parameters of the numerical reservoir model on the basis of the model A, setting the construction parameters as constant values, ensuring that each point of the reservoir is positioned at the same horizontal plane, eliminating the influence of gravity, establishing a model considering elasticity and capillary force (see figure 4), and recording the recovery ratio under the joint influence of the two acting forces as RElastic force + capillary force;
Running the model, wherein the oil reservoir recovery ratio is influenced by two acting forces of elastic force and capillary force and is recorded as RElastic force + capillary force,RElastic force + capillary forceThe time dependence is shown in FIG. 5.
Thirdly, deleting the curve data of the capillary force experiment on the basis of the model A, eliminating the influence of the capillary force, establishing a model considering the elastic force and the gravity, recording the model C, and recording the recovery ratio under the common influence of the two acting forces as RElastic force + gravity,RElastic force + gravityThe time dependence is shown in FIG. 6.
The influence of elastic force, gravity and capillary force on the recovery ratio in the development stage can be obtained by comparing the models A, B, C pairwise and making a difference on the extraction degree at the same development time.
The effect of gravity on recovery can be obtained by comparing model A with model B, RGravity forceModel a-model B | ═ RElastic force + gravity + capillary force-RElastic force + capillary force;
The effect of capillary forces on recovery can be obtained by comparing model A with model C, RCapillary forceModel a-model C | ═ RElastic force + gravity + capillary force-RElastic force + gravity;
With RElastic forceIndicating the effect of elastic force on the recovery factor,Relastic force=RElastic force + gravity + capillary force-RGravity force-RCapillary force。
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent structures or equivalent flow transformations made by using the contents of the specification and the drawings, or applied directly or indirectly to other related systems, are included in the scope of the present invention.