Ratio of water production rate at surface
to
liquid production rate at surface :
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Y_w=\frac{q_W}{q_L} |
It relates to Water-Oil Ratio (WOR) as:
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Y_w=\frac{1}{1+q_O/q_W}=\frac{{\rm WOR}}{1+{\rm WOR}} |
The simplest way to model the watercut in a given well is the Water Fractional Flow:
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{\rm Y_{wm}} = \frac{1}{1 + \frac{K_{ro}}{K_{rw}} \cdot \frac{ \mu_w}{\mu_o} \cdot \frac{B_w}{B_o} } |
which provides a good estimate when the drawdown is much higher than delta pressure from gravity and capillary effects.
Model
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requires accurate input on reservoir saturation.
The model
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can also be used in gross field
production analysis and in this case the average reservoir saturation can be assumed homogeneous:
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s_w(t) = s_{wi} + (1-s_{wi}-s_{or}) \cdot \rm RF(t)/E_S |
