Труды сотрудников ИВМ СО РАН

[Text] : статья / M.Desroche [et al.] // J. Geophys. Res-Space Phys. - 2013. - Vol. 118, Is. 6. - P3087-3095, DOI 10.1002/jgra.50294. - Cited References: 43. - The authors thank Chris Arridge for initially suggesting this project. The authors are thankful to Adam Masters, Bob Ergun, Jack Gosling, Martin Goldman, and Dmitri Uzdensky for helpful discussions and guidance. This work was supported by NASA's NESSF program. N.V. Erkaev acknowledges support by the RFBR grant No 12-05-00152-a. . - 9. - ISSN 2169-9380РУБ Astronomy & Astrophysics

Аннотация: Using idealized models of the magnetosheath and magnetospheric magnetic fields, plasma densities, and plasma flow, we test for the steady state viability of processes mediating the interaction between the solar wind and the magnetosphere of Saturn. The magnetopause is modeled as an asymmetric paraboloid with a standoff distance of approximate to 25R(S). We test where on the magnetopause surface largescale reconnection may be affected by either a shear flow or diamagnetic drift due to a pressure gradient across the magnetopause boundary. We also test for the onset of the KelvinHelmholtz instability. We find that, for the solar wind and magnetosphere states considered, reconnection is inhibited on the dawn flank due to the large shear flows in this region. Additionally, most of the dawn and dusk equatorial region of the magnetopause is KelvinHelmholtz unstable, due to the presence of the dense magnetospheric plasma sheet and weak magnetic fields on either side of the magnetopause. This study is a followup to a previously published study of the solar wind interaction with Jupiter's magnetosphere.


Доп.точки доступа:
Desroche, M.; Bagenal, F.; Delamere, P.A.; Erkaev, N.V.; Еркаев, Николай Васильевич; NASA's NESSF program; RFBR [12-05-00152-a]

[Text] / U.V. Amerstorfer [et al.] // Phys. Plasmas. - 2010. - Vol. 17, Is. 7. - Ст. 72901, DOI 10.1063/1.3453705. - Cited References: 26. - This work was supported by the FWF under Project No. P21051-N16 and also by the RFBR under Grant No. 09-05-91000-ANF_a. . - ISSN 1070-664XРУБ Physics, Fluids & Plasmas

Аннотация: Results of two-dimensional nonlinear numerical simulations of the magnetohydrodynamic Kelvin-Helmholtz instability are presented. A boundary layer of a certain width is assumed, which separates the plasma in the upper layer from the plasma in the lower layer. A special focus is given on the influence of a density increase toward the lower layer. The evolution of the Kelvin-Helmholtz instability can be divided into three different phases, namely, a linear growth phase at the beginning, followed by a nonlinear phase with regular structures of the vortices, and finally, a turbulent phase with nonregular structures. The spatial scales of the vortices are about five times the initial width of the boundary layer. The considered configuration is similar to the situation around unmagnetized planets, where the solar wind (upper plasma layer) streams past the ionosphere (lower plasma layer), and thus the plasma density increases toward the planet. The evolving vortices might detach around the terminator of the planet and eventually so-called plasma clouds might be formed, through which ionospheric material can be lost. For the special case of a Venus-like planet, loss rates are estimated, which are of the order of estimated loss rates from observations at Venus. (C) 2010 American Institute of Physics. [doi:10.1063/1.3453705]


Доп.точки доступа:
Amerstorfer, U.V.; Erkaev, N.V.; Еркаев, Николай Васильевич; Taubenschuss, U.; Biernat, H.K.

[Text] / B.Harris [et al.] // Ann. Geophys. - 2013. - Vol. 31, Is. 10. - P1779-1789, DOI 10.5194/angeo-31-1779-2013. - Cited References: 26. - Work at UNH is supported by NASA Grants NNX10AQ29G and NNX13AP39G. N. V. Erkaev is supported by grant No. 12-05-00152-a from the Russian Foundation of Basic Research. . - ISSN 0992-7689РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: Acceleration of magnetosheath plasma resulting from the draping of the interplanetary magnetic field (IMF) around the magnetosphere can give rise to flow speeds that exceed that of the solar wind (V-SW) by up to similar to 60%. Three case event studies out of 34 identified events are described. We then present a statistical study of draping-related accelerations in the magnetosheath. Further, we compare the results with the recent theory of Erkaev et al. (2011, 2012). We present a methodology to help distinguish draping-related accelerations from those caused by magnetic reconnection. To rule out magnetopause reconnection at low latitudes, we focus mainly on the positive B-z phase during the passage of interplanetary coronal mass ejections (ICMEs), as tabulated in Richardson and Cane (2010) for 1997-2009, and adding other events from 2010. To avoid effects of high-latitude reconnection poleward of the cusp, we also consider spacecraft observations made at low magnetic latitudes. We study the effect of upstream Alfven Mach number (M-A) and magnetic local time (MLT) on the speed ratio V/V-SW. The comparison with theory is good. Namely, (i) flow speed ratios above unity occur behind the dawn-dusk terminator, (ii) those below unity occur on the dayside magnetosheath, and (iii) there is a good general agreement in the dependence of the V ratio on M-A.


Доп.точки доступа:
Harris, B.; Farrugia, C.J.; Erkaev, N.V.; Еркаев, Николай Васильевич; Torbert, R.B.; NASA [NNX10AQ29G, NNX13AP39G]; Russian Foundation of Basic Research [12-05-00152-a]

[Text] / I. L. Arshukova, N. V. Erkaev, H. K. Biernat // Ann. Geophys. - 2004. - Vol. 22, Is. 3. - P993-999. - Cited References: 16 . - ISSN 0992-7689РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: This paper deals with nonsteady perturbations of the magnetosheath parameters which are related to variations of the interplanetary magnetic field from north to south under a constant solar wind dynamic pressure. The magnetic field changes its direction within a thin layer which is convected with the plasma from the bow shock to the ionopause. In the course of time, this current layer is amplified during its motion towards the magnetopause. The intensity of the current is increasing, the layer thickness is decreasing, and the gradients of parameters are becoming much sharper while the layer is approaching the magnetopause. The curvature radius of this layer is decreasing while it is draping around the magnetopause. This curved layer structure with reversed magnetic field in the magnetosheath is found to be unstable with respect to the interchange instability. The growth rate of the instability is obtained for different positions of the layer.


Доп.точки доступа:
Arshukova, I.L.; Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.

[Text] / I. L. Arshukova [et al.] ; ed. E. Kallio // PLANETARY ATMOSPHERES, IONOSPHERES AND PLASMA INTERACTIONS. Ser. ADVANCES IN SPACE RESEARCH : PERGAMON-ELSEVIER SCIENCE LTD, 2004. - Vol. 33: 2nd World Space Congress/34th COSPAR Scientific Assembly (OCT 10-19, 2002, HOUSTON, TEXAS), Is. 2. - P182-186, DOI 10.1016/j.asr.2003.04.015. - Cited References: 12 . - ISBN 0273-1177РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: Within the magnetohydrodynamic (MHD) approach, the interchange instability is studied for the subsolar magnetosheath of Venus. The instability analysis considers the profiles of magnetic field and plasma parameters between the bow shock and the ionopause which are obtained from the numerical MHD solution of the solar wind flow around the ionosphere. With the Fourier transformations, the linearized MILD equations are reduced to a second-order differential equation for the total pressure perturbation as a function of the normal distance from the ionopause. This equation is integrated numerically, and the interchange instability growth rate is obtained as a function of the wave number. The instability growth time is found to be smaller than the time scale of magnetic barrier formation. (C) 2003 COSPAR. Published by Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Arshukova, I.L.; Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.; Vogl, D.F.; Kallio, E. \ed.\

[Text] / N. V. Erkaev [et al.] // STREAMERS, SLOW SOLAR WIND, AND THE DYNAMICS OF THE MAGNETOSPHERE. Ser. ADVANCES IN SPACE RESEARCH : PERGAMON-ELSEVIER SCIENCE LTD, 2004. - Vol. 33: 2nd World Space Congress/34th COSPAR Scientific Assembly (OCT 10-19, 2002, HOUSTON, TX), Is. 5. - P784-788, DOI 10.1016/S0273-1177(03)00646-X. - Cited References: 13 . - ISBN 0273-1177РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: The interplanetary magnetic field is enhanced in a thin layer near the magnetopause which is called the magnetic barrier or plasma depletion layer. The magnetic energy stored in the magnetic barrier can be released during the process of magnetic field reconnection. Using ideal magnetohydrodynamics and assuming a sudden decrease of the magnetic field near the magnetopause due to the reconnection pulse, we analyze the model variations of the plasma parameters and the magnetic field at the magnetosheath. For a given reconnection rate and calculated parameters of the magnetic barrier, we derive the duration of a reconnection pulse as a function of the solar wind parameters. (C) 2003 COSPAR. Published by Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Farrugia, C.J.; Biernat, H.K.; Langmayr, D.

[Text] / H. K. Biernat, N. V. Erkaev, C. J. Farrugia // PLANETARY MAGNETOSPHERES. Ser. ADVANCES IN SPACE RESEARCH : ELSEVIER SCIENCE BV, 2001. - Vol. 28: D3 1/C3 3 Symposium of COSPAR Scientific Commission D held at the 33rd COSPAR Scientific Assembly (JUL, 2000, WARSAW, POLAND), Is. 6. - P833-839, DOI 10.1016/S0273-1177(01)00525-7. - Cited References: 12 . - ISBN 0273-1177РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: We use the "magnetic string" approach to integrate the dissipationless MHD equations for a 3-D flow around planetary obstacles, and apply it to some aspects of the flow in the magnetosheath of Venus. Our method has both analytical and numerical components, and is particularly suited to study the structure of the magnetic barrier (depletion layer). Including pick-up processes, we study the contribution to the structure of the Venus magnetosheath made by the pick-up ions. As one main conclusion, we show that the used method leads to a stand-off bow shock position which in good agreement with observations. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.


Доп.точки доступа:
Biernat, H.K.; Erkaev, N.V.; Еркаев, Николай Васильевич; Farrugia, C.J.

[Text] / N. V. Erkaev [et al.] // PLANETARY MAGNETOSPHERES. Ser. ADVANCES IN SPACE RESEARCH : ELSEVIER SCIENCE BV, 2001. - Vol. 28: D3 1/C3 3 Symposium of COSPAR Scientific Commission D held at the 33rd COSPAR Scientific Assembly (JUL, 2000, WARSAW, POLAND), Is. 6. - P873-877, DOI 10.1016/S0273-1177(01)00522-1. - Cited References: 16 . - ISBN 0273-1177РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: We study the solar wind flow in the Earth's magnetosheath using a three-dimensional, ideal magnetohydrodynamic (MHD) model with anisotropic plasma pressure. Four different closure relations are examined and compared with each other, i) The double adiabatic model; ii) the empirical relation with respect to the criterion of the anisotropic ion cyclotron instability; iii) the mirror instability criterion, and (iv) the combination of the mirror and the anisotropic ion cyclotron instability. Profiles of magnetic field strength and plasma parameters for the different closure relations are presented and compared with each other along the stagnation stream line between the shock and the obstacle. We find that the main body of the magnetosheath is mirror unstable. This is a reason to combine both, mirror and ion cyclotron instability criteria to close the ideal MHD model. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.


Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.; Vogl, D.F.; Farrugia, C.J.

[Text] / U. V. Mostl [et al.] // Icarus. - 2011. - Vol. 216, Is. 2. - P476-484, DOI 10.1016/j.icarus.2011.09.012. - Cited References: 27. - This work is supported by the Austrian Science Fund Project P21051-N16 and also by RFBR Grant No. 09-05-91000-ANF_a. H.L. and H.G. are supported by the Helmholtz Association through the research alliance "Planetary Evolution and Life" and by the Austrian Science Fund Project I199-N16. M.Z. and D.K. are supported by the Austrian Science Fund Project I193-N16. . - ISSN 0019-1035РУБ Astronomy & Astrophysics

Аннотация: The Kelvin-Helmholtz instability gained scientific attention after observations at Venus by the spacecraft Pioneer Venus Orbiter gave rise to speculations that the instability contributes to the loss of planetary ions through the formation of plasma clouds. Since then, a handful of studies were devoted to the Kelvin-Helmholtz instability at the ionopause and its implications for Venus. The aim of this study is to investigate the stability of the two instability-relevant boundary layers around Venus: the induced magnetopause and the ionopause. We solve the 2D magnetohydrodynamic equations with the total variation diminishing Lax-Friedrichs algorithm and perform simulation runs with different initial conditions representing the situation at the boundary layers around Venus. Our results show that the Kelvin-Helmholtz instability does not seem to be able to reach its nonlinear vortex phase at the ionopause due to the very effective stabilizing effect of a large density jump across this boundary layer. This seems also to be true for the induced magnetopause for low solar activity. During high solar activity, however, there could occur conditions at the induced magnetopause which are in favour of the nonlinear evolution of the instability. For this situation, we estimated roughly a growth rate for planetary oxygen ions of about 7.6 x 10(25) s(-1), which should be regarded as an upper limit for loss due to the Kelvin-Helmholtz instability. (C) 2011 Elsevier Inc. All rights reserved.


Доп.точки доступа:
Mostl, U.V.; Erkaev, N.V.; Еркаев, Николай Васильевич; Zellinger, M.; Lammer, H.; Groller, H.; Biernat, H.K.; Korovinskiy, D.

[Text] / I. I. Ryzhkov, A. V. Minakov // Int. J. Heat Mass Transf. - 2014. - Vol. 77. - P956-969, DOI 10.1016/j.ijheatmasstransfer.2014.05.045. - Cited References: 44. - This work is supported the Krasnoyarsk Regional Foundation of Scientific and Technical Activity (Grant No. 02/13) and the Russian President Grant No. MK-6296.2013.8. . - ISSN 0017-9310. - ISSN 1879-2189РУБ Thermodynamics + Engineering, Mechanical + Mechanics

Аннотация: Laminar convective heat transfer of water-alumina nanofluid in a circular tube with uniform heat flux is investigated numerically on the basis of two-component model, which takes into account nanoparticle transport by diffusion and thermophoresis. A new expression for thermophoretic mobility is suggested on the basis of existing experimental results and theoretical concepts. It is shown that thermophoresis leads to a significant reduction of nanoparticle volume fraction in the boundary layer near the wall. The corresponding viscosity reduction causes the velocity increase near the wall and flattening of velocity profile near the tube axis to keep the mass flow rate constant. The decrease of wall shear stress leads to the decrease of the required pressure drop. The calculations for two-component model provide higher values of the local and average heat transfer coefficients in comparison with the one-component model. The difference does not exceed 10% and decreases with increasing the thermal Peclet number. The calculations for one-component model show the independence of local and average Nusselt numbers on the nanoparticle volume fraction. The results for two-component model predict the increase of Nusselt number when the thermophoretic effect becomes stronger. The effectiveness of water-alumina nanofluid is analyzed by plotting the average heat transfer coefficient against the required pumping power. It is shown that the nanofluid shows better performance than the base fluid in the range of low pumping power and, correspondingly, low inlet velocity. (C) 2014 Elsevier Ltd. All rights reserved.

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Держатели документа:
[Ryzhkov, Ilya I.] SB RAS, Inst Computat Modelling, Krasnoyarsk 660036, Russia
[Minakov, Andrey V.] Siberian Fed Univ, Inst Engn Phys & Radio Elect, Krasnoyarsk 660041, Russia
ИВМ СО РАН

Доп.точки доступа:
Ryzhkov, I.I.; Рыжков, Илья Игоревич; Minakov, A.V.; Минаков, Андрей Викторович; Krasnoyarsk Regional Foundation of Scientific and Technical Activity [02/13]; Russian President Grant [MK-6296.2013.8]

[Text] / S. V. Kozlova, I. I. Ryzhkov // Eur. Phys. J. E. - 2014. - Vol. 37, Is. 9. - Ст. 87, DOI 10.1140/epje/i2014-14087-0. - Cited References: 44. - The authors are grateful to Dr. A. V. Minakov for assistance in ANSYS Fluent numerical calculations. This work is supported the Krasnoyarsk Regional Foundation of Scientific and Technical Activity (Grant 02/13). . - ISSN 1292-8941. - ISSN 1292-895XРУБ Chemistry, Physical + Materials Science, Multidisciplinary + Physics, Applied + Polymer Science

Аннотация: In this paper, laminar convective heat transfer of water-alumina nanofluid in a circular tube with uniform heat flux at the tube wall is investigated. The investigation is performed numerically on the basis of two-component model, which takes into account nanoparticle transport by diffusion and thermophoresis. Two thermal regimes at the tube wall, heating and cooling, are considered and the influence of nanoparticle migration on the heat transfer is analyzed comparatively. The intensity of thermophoresis is characterized by a new empirical model for thermophoretic mobility. It is shown that the nanoparticle volume fraction decreases (increases) in the boundary layer near the wall under heating (cooling) due to thermophoresis. The corresponding variations of nanofluid properties and flow characteristics are presented and discussed. The intensity of heat transfer for the model with thermophoresis in comparison to the model without thermophoresis is studied by plotting the dependence of the heat transfer coefficient on the Peclet number. The effectiveness of water-alumina nanofluid is analyzed by plotting the average heat transfer coefficient against the required pumping power. The analysis of the results reveals that the water-alumina nanofluid shows better performance in the heating regime than in the cooling regime due to thermophoretic effect.

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Держатели документа:
[Kozlova, Sofya V.
Ryzhkov, Ilya I.] Inst Computat Modelling SB RAS, Krasnoyarsk 660036, Russia
ИВМ СО РАН

Доп.точки доступа:
Kozlova, S.V.; Ryzhkov, I.I.; Рыжков, Илья Игоревич; Krasnoyarsk Regional Foundation of Scientific and Technical Activity [02/13]

/ V. B. Bekezhanova, O. N. Goncharova // Microgravity Sci. Technol. - 2019. - Vol. 31, Is. 4. - P357-376, DOI 10.1007/s12217-019-9691-4. - Cited References:38. - This work was partially supported by the Russian Foundation for Basic Research and the government of Krasnoyarsk region (project No. 18-41-242005). . - ISSN 0938-0108. - ISSN 1875-0494РУБ Engineering, Aerospace + Thermodynamics + Mechanics

Аннотация: The regimes of joint flows of the evaporating liquid and vapor-gas mixture in a 3D rectangular channel are studied with the help of a partially invariant solution for the convection equations. The effects of thermodiffusion and diffusive thermal conductivity in the gas-vapor phase are additionally taken into account in the governing equations and under interface conditions. A numerical simulation of the 3D fluid flows is carried out for the liquid-gas system like ethanol-nitrogen and HFE-7100-nitrogen under microgravity conditions. The influence of the thermal load, liquid layer thickness and heat-transfer liquid type on the structure of the fluid flows and evaporation characteristics is investigated. The solution allows one to describe the formation of longitudinal thermocapillary rolls observed in the experiments. The evaporative mass flow rate depends essentially on the thermophysical properties of the working liquid. Spatial size and a shape of thermal patterns are determined by the applied thermal load and they can be varied with the change in the liquid layer thickness. Topological structure of the flows (double or quadruple vortex composition) is defined by the combined influence of the thermocapillary and convective mechanisms and phase transition effects. The results discussed in the paper provide motivation for the development of a classification of the 3D flow regimes similar to the Napolitano's classification for 2D flows.

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Держатели документа:
RAS, Inst Computat Modelling SB, Dept Differential Equat Mech, Akademgorodok 50-44, Krasnoyarsk 660036, Russia.
Altai State Univ, Pr Lenina 61, Barnaul 656049, Russia.

Доп.точки доступа:
Bekezhanova, V. B.; Goncharova, O. N.; Russian Foundation for Basic Research; government of Krasnoyarsk region [18-41-242005]

/ I. I. Ryzhkov, A. S. Vyatkin, M. I. Medvedeva // J. Sib. Fed. Univ.-Math. Phys. - 2019. - Vol. 12, Is. 5. - P579-589, DOI 10.17516/1997-1397-2019-12-5-579-589. - Cited References:32. - The reported study was funded by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science, to the research project 18-48-242011 "Mathematical modelling of synthesis and ionic transport properties of conductive nanoporous membranes". . - ISSN 1997-1397. - ISSN 2313-6022РУБ Mathematics

Аннотация: The impact of potential applied to the conductive surface of nanoporous membrane on the membrane potential at zero current is investigated theoretically on the basis of two-dimensional Space-charge model. The membrane separates two reservoirs with different salt concentrations. It is shown that the variation of applied potential from negative to positive values results in the continuous change of membrane selectivity from cation to anion. For equal ion diffusion coefficients, the dependence of membrane potential on the applied potential is an odd function, while for different ion diffusion coefficients it is shifted along the applied potential axis due to contribution of diffusion potential enhanced by the induced charge effect. The decrease of pore radius results in the increase of ionic selectivity and steep transition between cation- selective and anion-selective states when the applied potential is changing.

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Держатели документа:
Inst Computat Modelling SB RAS, Akademgorodok 50-44, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Svobodny 79, Krasnoyarsk 660041, Russia.

Доп.точки доступа:
Ryzhkov, Ilya I.; Vyatkin, Anton S.; Medvedeva, Maria, I; Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science [18-48-242011]