Modern information technologies / 3. Software

Akmoldina Anara

Kostanay State University of A. Baitursynov, Kostanay

Approximate method for determining the coefficient of permeability of the layer at an elastic mode of oil

The general principle of non-stationary layers for study is that by changing the work of wells in the reservoir of artificially generated transients filtering and pressure is measured according to time in one or more wells. Based on data from the wells and flow rates of pressure change at certain points in the reservoir could receive information about the bed-permeability, piezoconductivity, about the location of the boundary layer, etc.

The easiest and most common way to create a non-stationary flow is stop one of the wells. Pressure curve of time, which is the study of reservoir, can be charged either in the hole, stopped or in another-a broken well (devices as well as piezometric). This assumes that the remaining amount during the study Wells change slightly.

Consider the one-dimensional axially symmetric motion (flat-radial)with elastic mode. Pressure distribution is defined as the solution to the heat equation in polar coordinates :

(1.1)

satisfying the initial condition

(1.2)

and the boundary conditions at .

Applications of particular importance is the task to which the borehole is constant flow. This is used in the most common ways of definition of parameters of the reservoir according to the observations of non-stationary flow to the wellbore. Suppose so

, (1.3)

where - the well's radius and .

Suppose that in the cylinder the pressure keeps a constant value equal to

(1.4)

This condition is met if, for example, the region borders vast well of water permeable layer. Let the set pressure, depending on the time at the well. That is

(1.5)

This means that the character expression in the left side of the equal sign is the first integral right of equality (1.14). Intuitively, it is clear that if