Hydraulic Properties Card Options (HYDT-KE)

Hydraulic Conductivity

If units of hydraulic conductivity are specified, the intrinsic permeability is computed assuming that the hydraulic conductivity was specified for the density and viscosity of  water at 25˚C and 1 atm.

Permeability

Permeability is computed as the product of the rock intrinsic permeability and the permeability reduction factor. The permeability tensor in STOMP-HYDT-KE has zero off-diagonal elements, requiring the specification of intrinsic permeability in the three principal axis directions, but intrinsic permeabilities for inactive principal directions are not required. For example, in a one-dimensional radial problem, only the intrinsic permeability in the radial direction needs to be specified. The intrinsic permeability can be specified with units of intrinsic permeability (e.g., m2, Darcy, mD) or with units of hydraulic conductivity (e.g., m/day, cm/hr).

Permeability reduction occurs via hydrate formation; therefore, effective permeabilities are a measure of the fluid mobility in the formation with the in-situ hydrate saturation. Conversion of the effective permeability to intrinsic permeability of the formation sandstone required the intrinsic porosity and hydrate saturation, according to Civan’s permeability-porosity relationship [1]:

References

1. Civan, F. 2001. “Scale effect on porosity and permeability: Kinetics, model, and correlation.” AIChE Journal, 47(2):271-287.