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Engineering topics

Yavorskaya, I. M.

Publications and source records attributed to Yavorskaya, I. M..

Convective flows of viscous fluid in spherical layers. Certain astrophysical applications

The convective stability of a viscous liquid in spherical layers is investigated taking into consideration rotation, the latitudinal temperature gradient, and shear flow. The results of calculating nonlinear convective motion in spherical layers are examined. A discussion is given of the applicability of the results obtained to studying convection in astrophysical objects.

Yavorskaya, I. M.↗

Nonlinear axisymmetric liquid currents in spherical annuli

A numerical analysis of non-linear axisymmetric viscous flows in spherical annuli of different gap sizes is presented. Only inner sphere was supposed to rotate at a constant angular velocity. The streamlines, lines of constant angular velocity, kinetic energy spectra, and spectra of velocity components are obtained. A total kinetic energy and torque needed to rotate the inner sphere are calculated as functions of Re for different gap sizes. In small-gap annulus nonuniqueness of steady solutions of Navier-Stokes equations is established and regions of different flow regime existences are found. Numerical solutions in a wide-gap annulus and experimental results are used in conclusions about flow stability in the considered range of Re. The comparison of experimental and numerical results shows close qualitative and quantitative agreement.

Astafyeva, N. M.↗

A possible explanation of the mechanism of formation of the equatorial jet on the surface of Jupiter

Formation of the equatorial jet of the Jovian surface was explained as a consequence of the Taylor-Proudman theorem. The asymptotic theory of motion of low viscosity fluids in a rotating spherical shear layer was included. The model shows the straited structure of the Jovian surface as the outflow of convective cells having the shape of axisymmetric rolls extended along the axis of rotation in the meridional direction. Depth of the layer was found to be of the order of 1000 kilometers.

Yavorskaya, I. M.↗

The internal structure of the convective envelope of the sun

An axisymmetric hydrodynamic model of the sun consisting of a core at radiant equilibrium and a convective envelope is studied with consideration of gravitational forces, rotation, turbulence effects, and electromagnetic forces. The dimensionless parameters that control the equations of plasma motion within the sun and the boundary conditions are investigated; estimates are given for these parameters on the basis of experimental data and the existing theoretical models. Stability conditions are derived for convective equilibrium, developed cellular convection, and developed turbulent convection with consideration of rotation and turbulent Reynolds stresses. These conditions characterize the possible physical state of the matter in the convective envelope. Using estimates of the dimensionless parameters and models of some of them, a method of successive approximations is proposed for solution of the problem as a whole.

Yavorskaya, I. M.↗

Thermal instability and energy relations in the convective envelopes of slowly rotating stars

The nonstationary convection that arises due to thermal instability in the envelopes of lower Main Sequence stars (and the sun in particular) is investigated. The convection that arises in the envelopes as a result of thermal instability is of nonstationary turbulent nature. It is shown that construction of a consistent model of the zones of turbulent convection in the stars requires the use of the complete heat flux equation with consideration of the terms that appear because of turbulence. Expressions for these additional terms in terms of averaged characteristics of the motion and eddy viscosity coefficients are derived on the basis of the Prandtl-Wasiutinsky theory.

Yavorskaya, I. M.↗