Effects Of Fluid Inertia on Sand Production from Perforated Oil Wells

Prediction of sand production in oil wells is generally conducted by using linear Darcy’s law as the constitutive equation for fluid flow. This law does not include the contribution of fluid inertial in pressure drop, and therefore is valid when flow velocity is low. In a perforated completion, considerable flow convergence occurs near the perforation tunnels, which makes it susceptible to inertia effects. In this paper, impacts of flow inertia on sand production from vertical cased-and-perforated oil wells are numerically analyzed. In this regard, ۳D coupled, poro-elastoplastic finite element methods with arbitrary Lagrangian-Eulerian (ALE) adaptive mesh approach are employed. Forchheimer’s law is used to incorporate high velocity flow effects into the analysis. A pressure gradient based erosion law is adapted for use as the sanding criterion. Helical symmetry of perforations, which usually is the case in practice, is utilized to achieve a more realistic but efficient simulation. Sanding response modifications due to inertia effects are presented for the considered range of parameters. The results highlight that high velocity flow causes additional hydrodynamic forces around the perforation tunnels, which in turn can result in more sand production. It is shown that ignoring the effects of inertia in perforated oil wells can lead to significantly lower predictions of both amount and rate of sand production.

کلیدواژه ها:

Sand production ، Inertia effects ، Forchheimer’s law ، Perforated completion