Why do we need to keep Kv/Kh at low values in the simulation models
During the upscaling processes from static models to dynamic models, many geologists and reservoir engineers are using Kv/Kh ratio of 1.0 similar to what has been measured in the lab forgetting the grid cells dimensions differences between the plugs and the simulator model cells, which are soo large that is required Kv/Kh to be readjusted to replicate the measurement.
Ingeniero de Analítica en Tecnologias de Subsuelo
1 年Bad Kv/Kh must be calculated based more in geological enviroment analysis with build up with partial penetration can be a useful model to assure that value.
Excellent common error.... actually assuming With isotropy; for the grid block a good approximation is to have Tx=Tz ; KxH =KzL or Kz=kxH/L,
Principal Reservoir Engineer (Simulation)
6 年@All, it doesn't matter if you are measuring Kv/Kh equal to 1.0 in the lab where the plugs dimensions in X, Y & Z are?almost equals, nevertheless; once you move to dynamic model with grid cells scale ratio of 1:1000 in X & Y vs. Z dimensions YOU HAVE TO use Kv/Kh less than 1.0 to replicate flow behavior.
Geosciences Advisor | Integrated reservoir characterization | Experience in Oil & Gas Reserves and Unitizations
6 年kv/kh is a scale-dependent property, in this sense any core measurement should be properly upscaled to grid scale before introducing in a simulator. I personally had best results for obtaining kv as an upscaled product of kh.
Senior Advisor at Rock Flow Dynamics
6 年The conundrum is nicely articulated above.? I'll add that we shouldn't under-estimate the role of 'geological common sense'.? If you are in a micaceous sandstone or a sandstone with thin shale laminae, then a Kv/Kh of 1 is most unlikely.? Characterizing carbonates can be tougher; but there may be clues on Kv/Kh from image logs or other tools with a directional component.