Summary
Many methods use radial and rectangular systems to interpret unsteady-state reservoir flow problems, but very little information is currently available for irregular drainage shapes. For many practical cases, however, the reservoir drainage shape is too complicated to be approximated by a circular or rectangular shape. This paper develops a means of predicting pressure-transient behavior in an irregularly shaped reservoir.
To generate a dimensionless-pressure-drop function, it is difficult to superpose the line-source solution of image wells in space for irregular drainage shapes. In this paper, the dimensionless-pressure-drop function is obtained by superposing the line-source solutions of image wells in time. The flow rates of image wells at each timestep are determined through solving a set of simultaneous linear algebraic equations that describe the conditions at the drainage boundary. The validity of this approach is proved by comparison of the calculated dimensionless-pressure-drop functions with literature values for various rectangular drainage shapes.
