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The Existence of Meromorphic Solutions to Non-Linear Delay Differential Equations
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作者 Mingyue Wu 《Open Journal of Applied Sciences》 2023年第12期2329-2342,共14页
In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational c... In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational coefficients, k is a positive integer. Under the assumption when above equations own transcendental meromorphic solutions with minimal hyper-type, we derive the concrete conditions on the degree of the right side of them. Specially, when w(z)=0 is a root of , its multiplicity is at most k. Some examples are given here to illustrate that our results are accurate. 展开更多
关键词 non-linear Delay Differential equations Painlevé Type equations Nevanlinna Theory Meromorphic Function Solutions Minimal Hypertype
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Establishment and application of logging saturation interpretation equation in vuggy reservoirs 被引量:3
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作者 孙文杰 李宁 +2 位作者 武宏亮 王克文 张宫 《Applied Geophysics》 SCIE CSCD 2014年第3期257-268,350,共13页
Vuggy reservoirs are the most common, albeit important heterogeneous carbonate reservoirs in China. However, saturation calculations using logging data are not well developed, whereas Archie method is more common. In ... Vuggy reservoirs are the most common, albeit important heterogeneous carbonate reservoirs in China. However, saturation calculations using logging data are not well developed, whereas Archie method is more common. In this study, electrical conduction in a vuggy reservoir is theoretically analyzed to establish a new saturation equation for vuggy reservoirs. We found that vugs have a greater effect on saturation than resistivity, which causes inflection in the rock-electricity curve. Using single-variable exPeriments, we evaluated the effects of rug size, vug number, and vug distribution on the rock-electricity relation. Based on the general saturation model, a saturation equation for vuggy reservoirs is derived, and the physical significance of the equation parameters is discussed based on the seepage-electricity similarity. The equation parameters depend on the pore structure, and vugs and matrix pore size distribution. Furthermore, a method for calculating the equation parameters is proposed, which uses nuclear magnetic resonance (NMR) data to calculate the capillary pressure curve. Field application of the proposed equation and parameter derivation method shows good match between calculated and experimental results, with an average absolute error of 5.8%. 展开更多
关键词 Vuggy reservoir SATURATION general solution saturation equation capillary pressure capillary pressure curve NMR rock electricity.
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ON THE HOLOMORPHIC SOLUTION OF NON-LINEAR TOTALLY CHARACTERISTIC EQUATIONS WITH SEVERAL SPACE VARIABLES 被引量:5
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作者 陈化 罗壮初 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期393-403,共11页
In this paper the authors study a class of non-linear singular partial differential equation in complex domain C-t x C-x(n). Under certain assumptions, they prove the existence and uniqueness of holomorphic solution n... In this paper the authors study a class of non-linear singular partial differential equation in complex domain C-t x C-x(n). Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near origin of C-t x C-x(n). 展开更多
关键词 non-linear singular partial differential equation holomorphic solution
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Analytical Solutions of System of Non-Linear Differential Equations in the Single-Enzyme, Single-Substrate Reaction with Non-Mechanism-Based Enzyme Inactivation 被引量:2
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作者 Govindhan Varadharajan Lakshmanan Rajendran 《Applied Mathematics》 2011年第9期1140-1147,共8页
A closed form of an analytical expression of concentration in the single-enzyme, single-substrate system for the full range of enzyme activities has been derived. The time dependent analytical solution for substrate, ... A closed form of an analytical expression of concentration in the single-enzyme, single-substrate system for the full range of enzyme activities has been derived. The time dependent analytical solution for substrate, enzyme-substrate complex and product concentrations are presented by solving system of non-linear differential equation. We employ He’s Homotopy perturbation method to solve the coupled non-linear differential equations containing a non-linear term related to basic enzymatic reaction. The time dependent simple analytical expressions for substrate, enzyme-substrate and free enzyme concentrations have been derived in terms of dimensionless reaction diffusion parameters ε, λ1, λ2 and λ3 using perturbation method. The numerical solution of the problem is also reported using SCILAB software program. The analytical results are compared with our numerical results. An excellent agreement with simulation data is noted. The obtained results are valid for the whole solution domain. 展开更多
关键词 non-linear Reaction equations ENZYME INACTIVATION HOMOTOPY PERTURBATION Method Time Dependent Analytical Solution
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Computer Methodologies for the Comparison of Some Efficient Derivative FreeSimultaneous Iterative Methods for Finding Roots of Non-Linear Equations 被引量:1
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作者 Yuming Chu Naila Rafiq +3 位作者 Mudassir Shams Saima Akram Nazir Ahmad Mir Humaira Kalsoom 《Computers, Materials & Continua》 SCIE EI 2021年第1期275-290,共16页
In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Conver... In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine.Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes,numerical experiments and CPU time-methodology.Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous iterative methods.Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical test examples.Numerical test examples,dynamical behavior and computational efficiency are provided to present the performance and dominant efficiency of the newly constructed derivative free family of simultaneous iterative method over existing higher order simultaneous methods in literature. 展开更多
关键词 non-linear equation iterative method simultaneous method basins of attractions computational efficiency
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Approximate Solution of Non-Linear Reaction Diffusion Equations in Homogeneous Processes Coupled to Electrode Reactions for CE Mechanism at a Spherical Electrode 被引量:2
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作者 A. Eswari S. Usha L. Rajendran 《American Journal of Analytical Chemistry》 2011年第2期93-103,共11页
A mathematical model of CE reaction schemes under first or pseudo-first order conditions with different diffusion coefficients at a spherical electrode under non-steady-state conditions is described. The model is base... A mathematical model of CE reaction schemes under first or pseudo-first order conditions with different diffusion coefficients at a spherical electrode under non-steady-state conditions is described. The model is based on non-stationary diffusion equation containing a non-linear reaction term. This paper presents the complex numerical method (Homotopy perturbation method) to solve the system of non-linear differential equation that describes the homogeneous processes coupled to electrode reaction. In this paper the approximate analytical expressions of the non-steady-state concentrations and current at spherical electrodes for homogeneous reactions mechanisms are derived for all values of the reaction diffusion parameters. These approximate results are compared with the available analytical results and are found to be in good agreement. 展开更多
关键词 non-linear Reaction/Diffusion equation HOMOTOPY PERTURBATION Method CE Mechanism Reduction of Order SPHERICAL ELECTRODES
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On Computer Implementation for Comparison of Inverse Numerical Schemes for Non-Linear Equations 被引量:1
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作者 Mudassir Shams Naila Rafiq +3 位作者 Nazir Ahmad Mir Babar Ahmad Saqib Abbasi Mutee-Ur-Rehman Kayani 《Computer Systems Science & Engineering》 SCIE EI 2021年第3期493-507,共15页
In this research article,we interrogate two new modifications in inverse Weierstrass iterative method for estimating all roots of non-linear equation simultaneously.These modifications enables us to accelerate the con... In this research article,we interrogate two new modifications in inverse Weierstrass iterative method for estimating all roots of non-linear equation simultaneously.These modifications enables us to accelerate the convergence order of inverse Weierstrass method from 2 to 3.Convergence analysis proves that the orders of convergence of the two newly constructed inverse methods are 3.Using computer algebra system Mathematica,we find the lower bound of the convergence order and verify it theoretically.Dynamical planes of the inverse simultaneous methods and classical iterative methods are generated using MATLAB(R2011b),to present the global convergence properties of inverse simultaneous iterative methods as compared to classical methods.Some non-linear models are taken from Physics,Chemistry and engineering to demonstrate the performance and efficiency of the newly constructed methods.Computational CPU time,and residual graphs of the methods are provided to present the dominance behavior of our newly constructed methods as compared to existing inverse and classical simultaneous iterative methods in the literature. 展开更多
关键词 non-linear equation inverse iterative method simultaneous method basins of attraction lower bound of convergence
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Double Elzaki Transform Decomposition Method for Solving Non-Linear Partial Differential Equations 被引量:1
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作者 Moh A. Hassan Tarig M. Elzaki 《Journal of Applied Mathematics and Physics》 2020年第8期1463-1471,共9页
In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Trans... In this paper, we discuss a new method employed to tackle non-linear partial differential equations, namely Double Elzaki Transform Decomposition Method (DETDM). This method is a combination of the Double ELzaki Transform and Adomian Decomposition Method. This technique is hereafter provided and supported with necessary illustrations, together with some attached examples. The results reveal that the new method is very efficient, simple and can be applied to other non-linear problems. 展开更多
关键词 Double Elzaki Transform Adomian Decomposition Method non-linear Partial Differential equations
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A Novel Empirical Equation for Relative Permeability in Low Permeability Reservoirs
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作者 葛玉磊 李树荣 曲珂馨 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1274-1278,共5页
In this paper, a novel empirical equation is proposed to calculate the relative permeability of low permeability reservoir. An improved item is introduced on the basis of Rose empirical formula and Al-Fattah empirical... In this paper, a novel empirical equation is proposed to calculate the relative permeability of low permeability reservoir. An improved item is introduced on the basis of Rose empirical formula and Al-Fattah empirical formula, with one simple model to describe oil/water relative permeability. The position displacement idea of bare bones particle swarm optimization is applied to change the mutation operator to improve the RNA genetic algorithm. The parameters of the new empirical equation are optimized with the hybrid RNA genetic algorithm(HRGA) based on the experimental data. The data is obtained from a typical low permeability reservoir well 54 core 27-1 in Gu Dong by unsteady method. We carry out matlab programming simulation with HRGA. The comparison and error analysis show that the empirical equation proposed is more accurate than the Rose empirical formula and the exponential model. The generalization of the empirical equation is also verified. 展开更多
关键词 Empirical equation Relative PERMEABILITY Hybrid RNA GENETIC algorithm Improved ITEM Low PERMEABILITY reservoirS BARE bones particle SWARM
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VALUE DISTRIBUTION OF MEROMORPHIC SOLUTIONS OF CERTAIN NON-LINEAR DIFFERENCE EQUATIONS
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作者 Minfeng CHEN Zongsheng GAO Jilong ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第4期1173-1184,共12页
In this article, we consider the non-linear difference equation(f(z + 1)f(z)-1)(f(z)f(z-1)-1) =P(z, f(z))/Q(z, f(z)),where P(z, f(z)) and Q(z, f(z)) are relatively prime polynomials in f(z) with rational coefficients.... In this article, we consider the non-linear difference equation(f(z + 1)f(z)-1)(f(z)f(z-1)-1) =P(z, f(z))/Q(z, f(z)),where P(z, f(z)) and Q(z, f(z)) are relatively prime polynomials in f(z) with rational coefficients. For the above equation, the order of growth, the exponents of convergence of zeros and poles of its transcendental meromorphic solution f(z), and the exponents of convergence of poles of difference △f(z) and divided difference △f(z)/f(z)are estimated. Furthermore, we study the forms of rational solutions of the above equation. 展开更多
关键词 non-linear DIFFERENCE equation MEROMORPHIC SOLUTION RATIONAL SOLUTION value dist ribution
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STABILITY OF GLOBAL MAXWELLIAN FOR NON-LINEAR VLASOV-POISSON-FOKKER-PLANCK EQUATIONS
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作者 Jie LIAO Qianrong WANG Xiongfeng YANG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期127-138,共12页
In this article, we establish the exponential time decay of smooth solutions around a global Maxwellian to the non-linear Vlasov–Poisson–Fokker–Planck equations in the whole space by uniform-in-time energy estimate... In this article, we establish the exponential time decay of smooth solutions around a global Maxwellian to the non-linear Vlasov–Poisson–Fokker–Planck equations in the whole space by uniform-in-time energy estimates. The non-linear coupling of macroscopic part and Fokker–Planck operator in the model brings new difficulties for the energy estimates, which is resolved by adding tailored weighted-in-v energy estimates suitable for the Fokker–Planck operator. 展开更多
关键词 non-linear Vlasov–Poisson–Fokker–Planck equation GLOBAL Maxwellian GLOBAL a priori estimates EXPONENTIAL convergence
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Travelling Wave Solution of the Fisher-Kolmogorov Equation with Non-Linear Diffusion
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作者 Muhammad Shakeel 《Applied Mathematics》 2013年第8期148-160,共13页
In this paper we study one-dimensional Fisher-Kolmogorov equation with density dependent non-linear diffusion. We choose the diffusion as a function of cell density such that it is high in highly cell populated areas ... In this paper we study one-dimensional Fisher-Kolmogorov equation with density dependent non-linear diffusion. We choose the diffusion as a function of cell density such that it is high in highly cell populated areas and it is small in the regions of fewer cells. The Fisher equation with non-linear diffusion is known as modified Fisher equation. We study the travelling wave solution of modified Fisher equation and find the approximation of minimum wave speed analytically, by using the eigenvalues of the stationary states, and numerically by using COMSOL (a commercial finite element solver). The results reveal that the minimum wave speed depends on the parameter values involved in the model. We observe that when diffusion is moderately non-linear, the eigenvalue method correctly predicts the minimum wave speed in our numerical calculations, but when diffusion is strongly non-linear the eigenvalues method gives the wrong answer. 展开更多
关键词 Fisher-Kolmogorov equation non-linear Diffusion TRAVELLING WAVE WAVE Speed Pulled FRONT Pushed FRONT
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THE FUNDAMENTAL EQUATIONS OF DYNAMICS USINGREPRESENTATION OF QUASI-COORDINATES IN THE SPACEOF NON-LINEAR NON-HOLONOMIC CONSTRAINTS
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作者 邱荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第11期0-0,0-0+0-0+0-0+0,共9页
The dot product of the bases vectors on the super-surface of the non-linear nonholonomic constraints with one order, expressed by quasi-coorfinates, and Mishirskiiequalions are regarded as the fundamental equations of... The dot product of the bases vectors on the super-surface of the non-linear nonholonomic constraints with one order, expressed by quasi-coorfinates, and Mishirskiiequalions are regarded as the fundamental equations of dynamics with non-linear andnon-holononlic constraints in one order for the system of the variable mass. From thesethe variant ddferential-equations of dynamics expressed by quasi-coordinates arederived. The fundamental equations of dynamics are compatible with the principle ofJourdain. A case is cited. 展开更多
关键词 non-linear non-holonomic constraints quasi-coordinates fundamental equations of dynamics
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Unconditionally Explicit Stable Difference Schemes for Solving Some Linear and Non-Linear Parabolic Differential Equation
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作者 Masaharu Nakashima 《Journal of Applied Mathematics and Physics》 2015年第11期1506-1521,共16页
We present the numerical method for solution of some linear and non-linear parabolic equation. Using idea [1], we will present the explicit unconditional stable scheme which has no restriction on the step size ratio k... We present the numerical method for solution of some linear and non-linear parabolic equation. Using idea [1], we will present the explicit unconditional stable scheme which has no restriction on the step size ratio k/h2 where k and h are step sizes for space and time respectively. We will also present numerical results to justify the present scheme. 展开更多
关键词 RUNGE-KUTTA Methods Method of LINES DIFFERENCE equation non-linear PDE
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An Analysis of the Impact of Economic-Ecological Balance Mechanism Based on Non-Linear Partial Differential Equations on Land Financial Teaching Methods
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作者 Weiqing Wang Lezhu Zhang +2 位作者 Weikun Zhang Ling Tao Hanyuan Liang 《Journal of Geoscience and Environment Protection》 2018年第10期28-39,共12页
This paper clarifies the relationship between the flow paths of the corresponding ecological flows because of the ecological impact for land consolidation, using external energy methods to measure the external input o... This paper clarifies the relationship between the flow paths of the corresponding ecological flows because of the ecological impact for land consolidation, using external energy methods to measure the external input of the project area or the output of ecological products. The application for nonlinear estimation of partial differential equations to land consolidation, the project ecological flow and system efficiency were quantitatively calculated. It shows that the conflict between fairness and efficiency is caused under conditions and levels of value and ecological compensation mechanism is built as a criterion for this ecological economics. Based on the years of use of the land improvement project, the time evolution of regional net ecological value, natural resource dependence, renewable resource dependence, ecological output ratio, ecological carrying capacity and ecological sustainability after the implementation of the project was assessed. 展开更多
关键词 Economic ECOLOGICAL BALANCE Mechanism non-linear Partial equation
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Initial Boundary Value Problems for a Class of Non-linear Pseudo-parabolic Equation
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作者 GUO Hong-xia HAN Xian-jun 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期335-343,共9页
In this paper,the existence,the uniqueness,the asymptotic behavior and the non-existence of the global generalized solutions of the initial boundary value problems for the non-linear pseudo-parabolic equation ut-αuxx... In this paper,the existence,the uniqueness,the asymptotic behavior and the non-existence of the global generalized solutions of the initial boundary value problems for the non-linear pseudo-parabolic equation ut-αuxx-βuxxt=F(u)-βF (u)xx are proved,where α,β 0 are constants,F(s) is a given function. 展开更多
关键词 non-linear pseudo-parabolic equation initial boundary problem global existence and uniqueness of solutions asymptotic behavior NON-EXISTENCE
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Analytical solution of coupled non-linear second order differential equations in enzyme kinetics
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作者 Govindhan Varadharajan Lakshmanan Rajendran 《Natural Science》 2011年第6期459-465,共7页
The coupled system of non-linear second-order reaction differential equation in basic enzyme reaction is formulated and closed analytical ex-pressions for substrate and product concentra-tions are presented. Approxima... The coupled system of non-linear second-order reaction differential equation in basic enzyme reaction is formulated and closed analytical ex-pressions for substrate and product concentra-tions are presented. Approximate analytical me-thod (He’s Homotopy perturbation method) is used to solve the coupled non-linear differential equations containing a non-linear term related to enzymatic reaction. Closed analytical expres-sions for substrate concentration, enzyme sub-strate concentration and product concentration have been derived in terms of dimensionless reaction diffusion parameters k, and us-ing perturbation method. These results are compared with simulation results and are found to be in good agreement. The obtained results are valid for the whole solution domain. 展开更多
关键词 non-linear Reaction equationS Mathematical Modelling STEADY-STATE HOMOTOPY PERTURBATION Method Simulation
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Approximate analytical solution of non-linear reaction diffusion equation in fluidized bed biofilm reactor
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作者 Seetharaman Usha Shanmugarajan Anitha Lakshmanan Rajendran 《Natural Science》 2012年第12期983-991,共9页
A mathematical model for the fluidized bed biofilm reactor (FBBR) is discussed. An approximate analytical solution of concentration of phenol is obtained using modified Adomian decomposition method (MADM). The main ob... A mathematical model for the fluidized bed biofilm reactor (FBBR) is discussed. An approximate analytical solution of concentration of phenol is obtained using modified Adomian decomposition method (MADM). The main objective is to propose an analytical method of solution, which do not require small parameters and avoid linearization and physically unrealistic assumptions. Theoretical results obtained can be used to predict the biofilm density of a single bioparticle. Satisfactory agreement is obtained in the comparison of approximate analytical solution and numerical simulation. 展开更多
关键词 Fluidized BED BIOFILM Reactor non-linear Reaction Diffusion equation PHENOL EFFECTIVENESS Factor Modified Adomian Decomposition Method
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Oscillation Criteria of second Order Non-Linear Differential Equations
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作者 Hishyar Kh. Abdullah 《Open Journal of Applied Sciences》 2012年第4期120-122,共3页
In this paper we are concerned with the oscillation criteria of second order non-linear homogeneous differential equation. Example have been given to illustrate the results.
关键词 component OSCILLATORY SECOND order DIFFERENTIAL equationS non-linear.
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Prediction of oil recovery in naturally fractured reservoirs subjected to reinfiltration during gravity drainage using a new scaling equation
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作者 AGHABARARI Amirhossein GHAEDI Mojtaba RIAZI Masoud 《Petroleum Exploration and Development》 2020年第6期1307-1315,共9页
By comparing numerical simulation results of single-porosity and dual-porosity models,the significant effect of reinfiltration to naturally fractured reservoirs was confirmed.A new governing equation was proposed for ... By comparing numerical simulation results of single-porosity and dual-porosity models,the significant effect of reinfiltration to naturally fractured reservoirs was confirmed.A new governing equation was proposed for oil drainage in a matrix block under the reinfiltration process.Utilizing inspectional analysis,a dimensionless equation suitable for scaling of recovery curves for matrix blocks under reinfiltration has been obtained.By the design of experiments,test cases with different rock and fluid properties were defined to confirm the scope of the presented equation.The defined cases were simulated using a realistic numerical simulation approach.This method can estimate the oil amount getting into the matrix block through reinfiltration,help simulate the oil drainage process in naturally fractured reservoirs accurately,and predict the recovery rate of matrix block in the early to middle periods of production.Using the defined scaling equation in the dual-porosity model can improve the accuracy of the predicted recovery rate. 展开更多
关键词 naturally fractured reservoir gravity drainage reinfiltration scaling equation dual-porosity simulation inspectional analysis
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