The most accurate way to simulate gas expansion is conventional 3D full-field dynamic modelling where gas motion is treated as one of the fluid phases and accounts of geological gas fluid properties, relperm properties, heat exchange .
The analytical models usually assume:
Isothermal expansion | Uniform pressure depletion in Gas Cap |
---|---|
T = \rm const | p_{GC}(t) = p(t) |
which leads to the following equation for Gas Cap volume:
V_{GC}(t) = V_{GC}(0) \cdot \exp \left[ - \int_{p_i}^{p(t)} c_g(p) dp \right] |
In simple case when Z-factor is constant and \displaystyle c_g = \frac{1}{p} then:
V_{GC}(t) = V_{GC}(0) \frac{p_i}{p(t)} |
See Also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Field Study & Modelling / Gas Cap Expansion
[ Depletion ] [ Saturated oil reservoir ]