Normalised dimensionless difference between the sandface bottomhole pressure (BHP) and the sandface reservoir pressure
at the well-reservoir contact.
S_G = \frac{2 \pi \sigma}{q_t} \left[ p_{wf}(t) - p({\bf r}, t) |_{r = r_w} \right] |
where
| total sandface rate | |
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.
For the fractured vertical well the geometrical skin-factor is related to Fracture half-length
as:
S_G = - \ln \left(\frac{X_f}{2\, r_w} \right) |
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Well Testing / Pressure Testing
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