Liu Ci-qun

Exact solution for the compressible flow equations through a medium with triple-porosity

This paper obtains the exact solution for the unsteady radial flow equations of the slightly compressible liquid through a medium with triple-porosity by using the method of decomposition. This solution not only reveals the essential characters of the unsteady flow of liquid through a medium with multiple-porosity, but also comprises the existing primal results.

General second order fluid flow in a pipe

It is more satisfactory for fluid materials between viscous and elastic to introduce the fractional calculus approach into the constitutive relationship. This paper employs the fractional calculus approach to study second fluid flow in a pape. First, we derive the analytical solution which the derivate order is half and then with the analytical solution we verify the reliability of Laplace numerical inversion based on Crump algorithm for the problem, and finally we analyze the characteristics of second order fluid flow in a pipe by using Crump method. The results indicate that the more obvious the viscoelastic properties of fluid is, the more sensitive the depondence of velocity and stress on fractional derivative order is.

Analytical solutions for equations of unsteady flow of non-newtonian fluids in tube

This paper presents analytical solutions to the partial differential equations for unsteady flow of the second-order fluid and Maxwell fluid in tube by using the integral transform method. It can be used to analyse the behaviour of axial velocity and shear stress for unsteady flow of non-Newtonian visco-elastic fluids in tube, and to provide a theoretical base for the projection of pipe-line engineering.

Transient pressure of percolation through one dimension porous media with threshold pressure gradient

This paper studies the transient pressure of percolation during one production and one shutting in one dimension porous media with threshold pressure gradient, the differential equations are derived and solved with numerical computation. Basing on numerical solution, it is analyzed that: 1. the relation between the steady pressure at well bore (or at endpoint) and threshold pressure gradient, shut-in time, and the corresponding formulae are derived; 2. the regulation of transient pressure peak. The result is very useful and will help experiments and applications in the development of low permeability reservoirs with threshold pressure gradient.

Theory of fluid displacement in a medium with double porosity

Abstract The afterflooding problem in a naturally fractured reservoir has been one of the most interesting problems in reservoir engineering and dynamics of flow through porous media for more than a decade. In this paper the correct basic equation describing two-phase flow through a medium with double porosity is given; its thorough study has been done by using the method of characteristics. The essential nature of oil displacement by water from naturally fractured reservoirs has been revealed and clarified, thus giving a theoretical guide to efficiently producing oil from such reservoirs. This work can be considered as an extension of the well-known Buckley-Leverett theory of a medium with double porosity.

New Studying of Lattice Boltzmann Method for Two-Phase Driven in Porous Media

By using the interaction of particles, such as the physical principle of the same attract each other and the different repulse each other, a new model of Lattice Boltzmann to simulate the two-phase driven in porous media was discussed. The result shows effectively for the problem of two-phase driven in porous media. Furthermore, the method economizes on computer time, has less fluctuation on boundary surface and takes no average measure.

An analytical solution and analysis of characters for viscoelastic fluid flow in annular pipe

In this paper an analytical solution to flow of second order and Maxwell fluids in annular pipe by using Hankel integral transform is presented. A derived formula can be used to analyze the behavior of rotatory velocity and shear stress; since the parameters of material and the gap size of annular pipe explicitly appear in the analytical formula one can easily analyze their effection on the flow behavior. This solution can provide a theoretical base to drilling engineering and polymer shaping techniques. In addition, it can be used to analyze the flow characters in concentric cylinder rheometer and obtain material constants with curve fitting procedure. By investigation it is found that when outer cylinder makes uniform rotatory the history curve of velocity and stress of Maxwell fluid exhibit obliquerectangle wave and raw-wave oscillation respectively. The wave period and amplitude increase with material constant Ha. This conclusion may be of significance in practice.

Exact solution of unsteady axisymmetrical two-dimensional flow through triple porous media

This paper seeks for the line source and cylindrical plane source solutions of unsteady axisymmetrical two-dimensional flow through infinite and finite reservoirs with triple porosity. They not only reveal the essential characteristics of fractured reservoirs but also generalize and develop the existing primal results of homogeneous and porous media.Ref. [1] gives the line source solution of unsteady axisymmetrical two-dimensional flow in infinite reservoir with double porosity; in this paper we study the problem of flow through triple porous media.

Analytical solution of flow of second-order non-Newtonian fluids through annular pipes

This paper presents an analytical solution to the unsteady flow of the second-order non-Newtonian fluids by the use of intergral transformation method. Based on the numerical results, the effect of non-Newtonian coefficient Hc and other parameters on the flow are analysed. It is shown that the annular flow has a shorter characteristic time than the general pipe flow while the correspondent velocity, average velocity have a smaller value for a given Hc. Else, when radii ratio keeps unchanged, the shear stress of inner wall of annular flow will change with the inner radius compared with the general pipe flow and is always smaller than that of the outer wall.

Analytical solution of partial differential equations for radial transport of a solute in double porous media

The mathematical model for radial transport of a solute is summed up in this paper. The action of non-equilibrium linear adsorption, the double property of porous media and the decay of solute are considered. With the first kind of boundary condition, one finds the analytical solution of these equations by Laplace transform and calculates the dimensionless solution by FORTRAN program with DJS-040. The distribution and change of solute are evaluated and the solution under various limit cases is given. By numerical analysis, one obtains some valuable conclusions.