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Yu. Petrova

Publications and source records attributed to Yu. Petrova.

3 recordsLinked to original sources

Impact of dissipation ratio on vanishing viscosity solutions of the Riemann problem for chemical flooding model

The solutions for a Riemann problem arising in chemical flooding models are studied using vanishing viscosity as an admissibility criterion. We show that when the flow function depends non-monotonically on the concentration of chemicals, non-classical undercompressive shocks appear. The monotonic dependence of the shock velocity on the ratio of dissipative coefficients is proven. For that purpose we provide the classification of the phase portraits for the travelling wave dynamical systems and analyze the saddle-saddle connections.

math.AP

Optimal polymer slugs injection profiles

The graded viscosity banks technology (tapering) for polymer flooding is studied for several different models of mixing zones behavior. Depending on the viscosity function the limiting polymer injection profile is rigorously derived for the transverse flow equilibrium model, for the Koval model and for the Todd-Longstaff model. The potential gain in the polymer quantity compared to the profile with a finite number of slugs is numerically estimated.

math.CA

Velocity of viscous fingers in miscible displacement

The paper investigates the linear growth of the mixing zone during polymer slug injection into a water reservoir. The velocities of the slug front and of the boundaries of the mixing zone are analyzed as key parameters. Using two different numerical methods (finite volumes and finite elements), the impact of the slug size, reservoir dimensions, Peclet number, and viscosity curve shape on the corresponding velocities is examined. Notwithstanding the realization of the solution by two computational schemes, the simulation results coincide with sufficient accuracy. The numerically obtained velocities are compared with theoretical estimates within the transverse flow equilibrium approximation and Koval model. Based on the comparison pattern, recommendations are presented on the use of specific analytical methods for estimating the growth rate of the mixing zone depending on the characteristics of the polymer.

physics.flu-dyn