During the cementing process of oil wells, fluid loss to the formation can occur and compromise the entire operation. In this work, we perform numerical analysis of the cementing operation in oil wells, in presence of fluid loss zone. Fluid loss zones in oil wells are often observed in carbonatic reservoir, very common in Brazilian pre-salt layer. Its drainage effects impact not only on the well pressure balance, but also the cement curing process. A 2-D multi-species transient model is proposed and implemented in Python, using the finite element method. Simplified cylindrical Navier-Stokes equations are used to predict pressure, velocity, and cement concentration fields. Cement is modeled as a mixture of two chemical species: the dissolved cement modeled as a viscoplastic slurry and the filtrate water. A reference case is simulated fitting the proposed rheological model to slurry characterization curves from the literature. Finally a sensitivity analysis was performed, regarding the model rheological parameters, fluid loss flow rate and the slurry characteristic time.
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