If we are dealing with moderate permeability reservoir 10-200mD and have only few fractures observed in core how do you decide if it warrants double porosity or single porosity is sufficient for simulation modelling ?
There were only few sub-economic wells were drilled, they did not have any rapid WCT breakthroughs. Productivity wise to match wells production we may just use high side of poro-perm transform so making double porosity/perm model might not increase productivity significantly unless we assume more heavily fractured reservoir with large shape factor which might be difficult to justify.
The choice between single-porosity and double-porosity models depends on the nature of the porous medium and the specific objectives of the simulation:
Single-porosity models assume a homogeneous porous medium where fluid flow occurs through interconnected pores. This approach is suitable for reservoirs or formations where fractures do not significantly impact fluid movement.
Double-porosity models account for both matrix and fracture systems separately, recognizing that fractures provide high-permeability pathways while the matrix stores most of the fluid. This is useful for fractured reservoirs, geothermal systems, and karst formations where fluid exchange between fractures and matrix plays a crucial role.
Key factors influencing the decision:
Reservoir Characteristics – If fractures dominate fluid flow, a double-porosity model is preferable.
Simulation Objectives – If the goal is to capture rapid fluid movement through fractures while considering matrix storage, double-porosity is more appropriate.
Data Availability – Single-porosity models require fewer parameters, making them easier to calibrate when data is limited.
Computational Complexity – Double-porosity models are more complex and computationally demanding.
For a deeper dive into comparisons and applications, you can check out this study or this research.