Transient Flow Behavior of Horizontal Wells, Pressure Drawdown, and Buildup Analysis

Abstract

Four flow periods may occur during the transient behavior of a horizontal well. Drawdown and buildup equations describing the flow behavior of each of the four flow periods are given. Methods for analyzing data obtained from testing the well to determine permeability anisotropy in the drainage volume of the well, as well as the skin factor, are presented. The calculation procedures are illustrated by examples.

A density-diffusivity approach for the unsteady state analysis of natural gas reservoirs

“…Analytical solutions to these liquid equations are readily available in the form of type-curves, which have become one of the foundations of reservoir engineering analysis. Starting with the pioneering analytical solutions provided by Van Everdingen and Hurst (1949), the "liquid" pressure diffusivity equation have been extensively analyzed and solved for a myriad of reservoir models and boundary conditions for the case of oil systems, including the analysis of infinite-acting constant rate production in radial systems (Ramey, 1970;Gringarten et al, 1979;Bourdet et al, 1983a), hydraulic fractured wells (Cinco et al, 1978;Gringarten et al, 1974;Agarwal et al, 1979), naturally-fractured systems (Warren and Root, 1963;Bourdet et al, 1983b), horizontal wells (Giger et al, 1984;Odeh and Babu, 1990;Ozkan, 2001), among others. These applications have established the fundamental solutions to the "liquid" pressure diffusivity equation, and their results have been widely used in oil pressure transient analysis.…”

Prosta metoda określania przepuszczalności pokładów węgla w warunkach kopalnianych

“…Zależność p dr − p 0 od log t pokazano za pracą [7] Ponieważ ze względu na przyjęte warunki początkowe i brzegowe oraz liczne uproszczenia podane tutaj zależności różnią się od cytowanych w literaturze, zatem w dalszej czę-ści artykułu podajemy wyprowadzenie odpowiednich wzorów. Wyprowadzony wzór (1) dotyczy wczesnego przypływu radialnego i służyć może jedynie do określenia przepuszczalności i skin efektu dla krótkich czasów zatłaczania z powodu założenia nieograniczoności ośrodka porowatego.…”

Generalized inflow performance relationships for horizontal gas wells

“…The transient flow period provides engineers with an invaluable tool to determine reservoir parameters and well productivity. Therefore, it was the subject of many studies for many years (Clonts and Ramey, 1986;Ozkan et al, 1989;Odeh and Babu, 1990;Kuchuk et al, 1991). Kuchuk et al (1991) presented an analytical solution for transient pressure behavior of a horizontal well completed in an infinite anisotropic medium bounded above and below by horizontal planes (Fig.…”