arXiv subjects

Alexander V. Proskurin

Publications and source records attributed to Alexander V. Proskurin.

5 recordsLinked to original sources

arXiv2020

Mathematical modelling of an unstable bent flow using the selective frequency damping method

The selective frequency damping method was applied to a bent flow. The method was used in an adaptive formulation. The most dangerous frequency was determined by solving an eigenvalue problem. It was found that one of the patterns, steady-state or pulsating, may exist at some relatively high Reynolds numbers. The periodic flow occurs due to the instability of the steady-state flow. This numerical method is easy to use but requires a great deal of time for calculations.

physics.flu-dyn↗

arXiv2019

A numerical approach for transient magnetohydrodynamic flows

In the article the authors present a numerical method for modelling a laminar-turbulent transition in magnetohydrodynamic flows. The equations in the small magnetic Reynolds numbers approach is considered. Speed, pressure and electrical potential are decomposed to the sum of the state values and the finite amplitude perturbations. A solver based on the Nectar++ framework is described. The authors suggest to use of small-length local disturbances as a transition trigger. They can be imposed by blowing or electrical enforcing. The stability of the Hartmann flow and the flow in the bend are considered as examples.

physics.flu-dyn↗

arXiv2019

A spectral/hp element MHD solver

A new MHD solver, based on the Nektar++ spectral/hp element framework, is presented in this paper. The velocity and electric potential quasi-static MHD model is used. The Hartmann flow in plane channel and its stability, the Hartmann flow in rectangular duct, and the stability of Hunt's flow are explored as examples. Exponential convergence is achieved and the resulting numerical values were found to have an accuracy up to $10^{-12}$ for the state flows compared to an exact solution, and $10^{-5}$ for the stability eigenvalues compared to independent numerical results.

physics.comp-ph↗

arXiv2018

A MHD reverse flow in 90 degree bend

A two-dimensional flow in a 90 degree bent channel is considered. A magnetic field is uniform and parallel to inlet branch of the channel. A spectral/hp element method was used for liquid motion calculations. Three types of steady flows were detected. It was found that magnetic forces can suppress a pressure gradient and throw out liquid from the inlet, a relatively large reverse flow appears.

physics.flu-dyn↗

arXiv2016

An example of the Rvachev function method

We present a Rvachev function method with the Chebysev collocation for the stability analysis of fluid flow. The strategy is to construct an approximate solution that satisfies all boundary conditions exactly. As an example, we consider the stability problem of the two-dimensional flow of an incompressible viscous liquid near a circular cylinder. The results coincide well with the reference data. The method is simpler than the widely used spectral/hp element method, in particular because it does not require mesh generation, and the collocation algorithm does not handle the boundary conditions or any geometric information.

physics.flu-dyn↗