Page 329 - Principles of Applied Reservoir Simulation 2E

314 Principles of Applied Reservoir Simulation

30.2 Explicit Pressure Constraint Representation

Case \: Oil and/or Water Production Wells
We assume that flowing bottomhole pressures (PWF) and well PIDs are
specified for a pressure-constrained well. The oil and water rates in STB/D for
connection k are given by

V
PID (P n - PWF), (30.17)
Qnk =

and
A, n
(P - PWF), (30.18)
B
k
where the explicit pressure P" is used. If P" < PWF, the well is shut in. When
P" > PWF, Q ok and Q wk are calculated and then substituted into Eq. (30.3) to

Case 2: Gas Production Well
The laminar-inertial-turbulent (LIT) method may be used to represent a
gas production well. The LIT method entails fitting gas well test data to the
equation

aQ + bQ = i|r - t|f (30.19)

where
= pseudo-pressure corresponding to shut-in pressure
ty R
2
P R (psia / cp)
=
t|V pseudo-pressure corresponding to a specified well flowing
pressure /^(psiaVcp)
ag g = laminar flow
2
^(? g ~ inertial and turbulent flow
WINB4D employs user specified values of a, b, P wf, and a table of pseudo-
pressure versus pressure values to compute total gas well production rate as