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A property characterising agility of the fluid under pressure gradient gradient with account of reservoir permeability and dynamic fluid viscosity:
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In multiphase flow the concept of fluid mobility is not well-defined as phases may flow quite independently from each other and have different dynamic parameters fluid parameters (pressure and velocity).
But for relatively homogeneous multi-phase flow (phases may move at different speeds but different velocities but occupy the same reservoir space and have the same pressure) the multi-phase mobility may be defined by Perrine model:
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