Normalised dimensionless difference between the sandface bottomhole pressure (BHP)
and the
sandface r
eservoir pressure LaTeX Math Inline |
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body | \displaystyle p({\bf r}, t) |_{r = r_w} |
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at the
well-reservoir contact.
LaTeX Math Block |
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S_G = \frac{2 \pi \sigma}{q_t} \left[ p_{wf}(t) - p({\bf r}, t) |_{r = r_w} \right] |
where
It characterises the pressure drop at well-reservoir contact due to well-reservoir contact geometry.
The geometrical skin is negative for fractured wells and slanted.
It also negative for horizontal wells when lateral permeability is not much lower than vertical.
The geometrical skin is positive for limited entry wells.