Page 335 - Principles of Applied Reservoir Simulation 2E

320 Principles of Applied Reservoir Simulation

r = 0.28
(K y/K xf< + (K xIK/<

The remaining parameters are defined as:
K = horizontal permeability of connection k (md)
h - thickness of connection k (ft)
= wellbore radius (ft)
r w
S = dimensionless skin factor
In principle, the well flow index can be related to measured values. In practice,
however, the terms r e, S, and k ro /\1 0B 0 are seldom well known, especially for
a multiphase flowing well. As a matter of expediency, therefore, Eq. (31.2) is
often used to compute an initial estimate of PID. This value can then be
improved by adjusting it until the well rates computed by the simulator match
the initial observed well rates.

31.3 Horizontal Wells
There are many ways to estimate connection flow index PID for a
horizontal well [Joshi, 1991 ]. A PID value can be estimated for horizontal wells
in a manner similar to that for vertical wells by using the Joshi formula

pro, QMlOSKh

2 _ I L I
a+ . \ (31.3)
\ I 2 j
In ( h J +5
O
^^
( LI2 ) 2r wj
where

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