Page 244 - Principles of Applied Reservoir Simulation 2E

Introduction to WINB4D

WINB4D simulates isothermal, Darcy flow in up to three dimensions. It
assumes reservoir fluids can be described by up to three fluid phases (oil, gas,
and water) with physical properties that depend on pressure only. Gas is allowed
to dissolve in both the oil and water phases, A feature unique to WTNB4D is the
inclusion of compressional velocity and acoustic impedance calculations. These
reservoir geophysical calculations make it possible to track changes in seismic
variables as a function of time, which is the basis for 4D seismic analysis.
WINB4D was designed to run on Windows-based personal computers
with 486 or better math co-processors. This size simulator is well-suited for
learning how to use a reservoir simulator, developing an understanding of
reservoir management concepts, and for solving many types of reservoir
engineering problems. It is an inexpensive tool for performing studies that call
for more sophistication than is provided by analytical solutions, yet do not
require the use of full-featured commercial simulators.
WINB4D is a modified version of the black oil simulator BOAST II that
was published by the U.S. Department of Energy in 1987 [Fanchi, et al, 1987].
BOAST II was an improved version of BOAST, an implicit pressure-explicit
saturation (IMPES) simulator published by the U.S. Department of Energy in
1982 [Fanchi, et al., 1982]. There have been several modifications of BOAST
II published by the Bartlesville Project Office of the U.S. Department of Energy.
WINB4D is based on BOAST II.
A comparison of differences between BOAST II and WINB4D is given
in Tables 23-1 and 23-2.The first table shows that a variety of useful geophysical

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