Chapter 3 - Transient Well Testing Methods for Horizontal Oil Wells

Abstract

Transient pressure analysis of horizontal wells is more complex than that of vertical wells because well models assume that horizontal wells are perfectly horizontal and are parallel to the top and bottom boundaries of the reservoir, and it is difficult to estimate exact production length of a long horizontal well. This chapter describes steady-state fluid flow through a reservoir. Mathematical equations are included for horizontal oil wells. In oil wells, pressure, instead of pressure-squared and pseudo-pressure methods, are normally used to describe the relationship between pressures and flow rates. This chapter summarizes a discussion of horizontal wells in oil reservoirs. Horizontal wells enhance the drainage area in a given time period, while in-high permeability oil reservoirs, they reduce near-wellbore turbulence and enhance well deliverability. Horizontal wells have high potential in oil reservoirs. This chapter also includes the influence of turbulence and turbulence identification, comparison of inflow performance responses in vertical and horizontal oil wells, and time and transient pressure response analysis equations related to each of the flow regimes to solve for specific reservoir parameters using drawdown and buildup tests.