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БЕЗОПАСНОСТЬ — КЛЮЧЕВОЙ МОМЕНТ ВОЗРОЖДЕНИЯ ЯДЕРНОЙ ЭНЕРГЕТИКИ
(1993) Феоктистов Л. П.
Около десяти лет назад в Институте атомной энергии им. И.В. Курчатова широко обсуждались вопросы строительства атомных электростанций (АЭС) с тремя предположениями о темпах развития: высоком, среднем, низком (по среднему прогнозу до 150 ГВт(э) суммарной мощности АЭС). Сейчас можно констатировать, что темпы развития оказались ниже самых низких прогнозированных. И даже само слово "развитие" следует взять в кавычки. И дело не только в том, что Россия переживает глубокую экономическую реформу и реорганизацию производст ва. Спад в ядерной энергетике произошел раньше. Его причина заключена в реакции общества на Чернобыльскую аварию. Открытие ядерной энергии — высочайшее достижение мировой науки, его нельзя ни закрыть, ни забыть, его нужно научиться использовать не во вред, а на пользу человеку.
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ИНФОРМАЦИОННЫЕ УСЛУГИ БИБЛИОТЕКИ
(МИФИ, 2003) Стукалова, Т. Н.; Стукалова, Татьяна Николаевна
В докладе рассказывается об информационных услугах университета, построенных на новых информационных технологиях.
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ИНФОРМАЦИОННОЕ ОБЕСПЕЧЕНИЕ УЧЕБНОГО ПРОЦЕССА И НАУЧНОЙ ДЕЯТЕЛЬНОСТИ УНИВЕРСИТЕТА
(НИЯУ МИФИ, 2004) Стукалова, Т. Н.; Капочкина, И. П.; Капочкина, Ирина Петровна; Стукалова, Татьяна Николаевна
В докладе рассказывается об электронных ресурсах, созданных и постоянно пополняемой библиотекой, об обеспечении доступа к информации по основным научным и учебным направлениям деятельности МИФИ всем категориям пользователей.
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Modeling of electromagnetic stirring in the DC casting of aluminum with ANSYS
(2013) Pavlov, E.; Timofeev, V.; Bogovalov, S.; Tronin, I.; Kislov, V.; Тронин, Иван Владимирович; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович
Modeling of the magnetohydrodynamical (MHD) and thermodynamical processes during the industrial scale Direct Chill (DC) casting of aluminum slabs is performed using a combination of ANSYS/CFX and ANSYS/EMAG software. The electromagnetic field is modeled through ANSYS/EMAG, while hydrodynamic and thermodynamic processes are modeled through ANSYS/CFX. Both packages were modified in order to calculate MHD flows in the liquid pool that forms during aluminum DC casting, and they were unified into a software combination that provides simultaneous simulation of all the above processes. The simulation shows that the electromagnetic stirring of the molten aluminum changes the shape of the solidification front (solid-liquid interface) very dramatically, namely it becomes significantly flatter. This effect should improve the internal structure of aluminum DC slabs and allows us to increase the casting velocity.
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Verification of numerical codes for modeling of the flow and isotope separation in gas centrifuges
(2013) Bogovalov, S. V.; Borisevich, V. D.; Borman, V. D.; Kislov, V. A.; Tronin, I. V.; Tronin, V. N.; Тронин, Иван Владимирович; Боговалов, Сергей Владимирович; Борисевич, Валентин Дмитриевич; Кислов, Владимир Александрович
A new method for verification of numerical codes for modeling of gas flow and isotope separation in gas centrifuges (GC) is proposed. The method is based on a semi-analytical solution of the problem of gas circulation in the rotating cylinder (rotor) with an infinite length. The problem is solved for a small amplitude perturbation of the rigid rotation of the gas. It is assumed that the circulation drives, thermal or mechanical origin, vary with the coordinate along the rotation axis harmonically. Solution of the system of equations in partial derivatives is reduced to the solution of the system of ordinary differential equations which can be solved with any accuracy by well known methods. The gas circulation in the solution consists of the system of vortexes periodically located along the rotation axis. The comparison of the semi-analytical solution with the numerical one is possible provided that periodical boundary conditions are specified at the end caps of the rotor of GC. Special attention is paid to the case when the conventional rigid wall boundary conditions are specified at the end caps of the rotor. It is shown that the developed semi-analytical solution can be applied for the verification of the numerical codes in this case as well.
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Verification of software codes for simulation of unsteady flows in a gas centrifuge
(2013) Abramov, V. A.; Bogovalov, S. V.; Kislov, V. A.; Yupatov, S. V.; Tronin, V. N.; Tronin, I. V.; Borman, V. D.; Borisevich, V. D.; Борисевич, Валентин Дмитриевич; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович; Тронин, Иван Владимирович
A simple semi-analytical solution is proposed for the problem of an unsteady gas flow in a gas centrifuge. The circulation in the centrifuge is driven by a source/sink of energy and by an external force (deceleration/acceleration of the gas rotation) acting on the gas at a given frequency. In the semi-analytical solution, the rotor is infinite, while the given forces vary harmonically with a given wave-length along the axial coordinate. As a result, the unsteady flow problem is reduced to a system of ordinary differential equations, which can be quickly solved to any prescribed accuracy. This problem is proposed for verifying numerical codes designed for the simulation of unsteady processes in gas centrifuges. A similar unsteady problem is solved numerically, in which case the cylinder is finite with the rotor length equal to the wavelength of the external force along the axis of rotation. The periodicity of the solution is set at end faces of the cylinder. As an example, the semi-analytical solution is compared with the numerical one obtained with these boundary conditions. The comparison confirms that the problem formulations are equivalent in both cases.
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On a Formula to Evaluate the Separative Power of Long Gas Centrifuges [
(2014) Borisevich, V. D.; Borman, V. D.; Bogovalov, S. V.; Kislov, V. A.; Tronin, V. N.; Tronin, I. V.; Abramov, V. I.; Yupatov, S. V.; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович; Борисевич, Валентин Дмитриевич; Тронин, Иван Владимирович
We discuss the possibility of applying the semi-empirical formula derived for evaluating the separative power of the Russian-type optimized gas centrifuge, with a rotor length about 1 m, to centrifugal machines of arbitrary length. It is demonstrated that the formula can adequately describe the dependence of a single gas centrifuge's performance on rotor peripheral rotation, length, and diameter for machines with lengths of up to 5 m. The comparison of the calculated values for separative power, obtained by numerical simulations of flow and diffusion in gas centrifuges with that of the URENCO machines, demonstrates satisfactory agreement. © 2014 Copyright Taylor and Francis Group, LLC. Acknowledgement: This work is supported by the Ministry of Education and Science of Russian Federation in the framework of the Federal Targeted Program Scientific and Pedagogical Staff for Innovative Russia for 2009-2013, State Contract No. 16.740.11.0536 (the project leader is Professor V. D. Borisevich).
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Gas Dynamics in Strong Centrifugal Fields/
(2015) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V.; Тронин, Иван Владимирович; Боговалов, Сергей Владимирович; Кислов, Владимир Александрович
Dynamics of waves generated by scopes in gas centrifuges (GC) for isotope separation is considered. The centrifugal acceleration in the GC reaches values of the order of 10(6)g. The centrifugal and Coriolis forces modify essentially the conventional sound waves. Three families of the waves with different polarisation and dispersion exist in these conditions. Dynamics of the flow in the model GC Iguasu is investigated numerically. Comparison of the results of the numerical modelling of the wave dynamics with the analytical predictions is performed. New phenomena of the resonances in the GC is found. The resonances occur for the waves polarized along the rotational axis having the smallest dumping due to the viscosity. Доп. точки доступа:_
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Waves in strong centrifugal fields: dissipationless gas
(2015) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V.; Тронин, Иван Владимирович; Боговалов, Сергей Владимирович; Кислов, Владимир Александрович
Linear waves are investigated in a rotating gas under the condition of strong centrifugal acceleration of the order 106g realized in gas centrifuges for separation of uranium isotopes. Sound waves split into three families of the waves under these conditions. Dispersion equations are obtained. The characteristics of the waves strongly differ from the conventional sound waves on polarization, velocity of propagation and distribution of energy of the waves in space for two families having frequencies above and below the frequency of the conventional sound waves. The energy of these waves is localized in rarefied region of the gas. The waves of the third family were not specified before. They propagate exactly along the rotational axis with the conventional sound velocity. These waves are polarized only along the rotational axis. Radial and azimuthal motions are not excited. Energy of the waves is concentrated near the wall of the rotor where the density of the gas is largest.
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Waves in strong centrifugal field
(2015) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V.; Тронин, Иван Владимирович; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович
Dynamics of waves generated by scopes in gas centrifuges (GC) for isotope separation is considered. The centrifugal acceleration in the GC reaches values of the order of 106g. The centrifugal and Coriolis forces modify essentially the conventional sound waves. Three families of the waves with different polarization and dispersion exist in these conditions. Dynamics of the flow in the model GC Iguasu is investigated numerically. Comparison of the results of the numerical modeling of the wave dynamics with the analytical predictions is performed. New phenomena of the resonances in the GC is found. The resonances occur for the waves polarized along the rotational axis having the smallest dumping due to the viscosity. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.
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Modeling of waves in the Iguasu gas centrifuge
(2015) Bogovalov, S. V.; Kislov, V. A.; Tronin, I .V.; Боговалов, Сергей Владимирович; Тронин, Иван Владимирович; Кислов, Владимир Александрович
2D axisymmetric transient flow induced by a pulsed braking force in the Iguasu gas centrifuge was simulated numerically. The computational domain consists of three cameras: top, working and bottom. The feed flow injected to the working camera, product and waste fluxes removed in the bottom and top cameras, respectively. The transient case is compared with the stationary case where the flow is excited by the stationery braking force. The braking forces averaged over the period of the rotation are equal each other in both cases. In the transient case the gas flux through the gap in the bottom baffle 15 % exceeds the flux in the stationary case for the same pressure and temperature. We argued that the waves reduce the pressure in the GC on the same 15 %. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.
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Verification of the Numerical Codes for Modelling of Gas Dynamics in Strong Centrifugal Field
(2015) Bogovalov, S. V.; Borisevich, V. D.; Borman, V. D.; Kislov, V. A.; Tronin, I. V.; Tronin, V. N.; Боговалов, Сергей Владимирович; Тронин, Иван Владимирович; Борисевич, Валентин Дмитриевич; Кислов, Владимир Александрович
A simple semi-analytical solution is proposed for the verification of numerical codes for modelling of unsteady gas flows in strong centrifugal fields. The gas flow is driven by a source/sink of energy and by an external force (deceleration/acceleration of the gas rotation) acting on the gas at a given frequency. In the semi-analytical solution, the rotor is infinite, while the given forces vary harmonically with a given wave-length along the axial coordinate. As a result, the unsteady flow problem is reduced to a system of ordinary differential equations, which can be quickly solved to any prescribed accuracy. A similar unsteady problem is solved numerically with the rotor length equal to the wavelength of the external force along the axis of rotation. The periodicity of the solution is prescribed at the end faces of the rotor. As an example, the semi-analytical solution is compared with the numerical ones obtained with different boundary conditions and mesh resolution in radial direction. The comparison confirms that the problem formulations are equivalent in both cases. The semi-analitical solution allows us to determine optimal mesh resolution and accuracy of the calculations.
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Method of verification of the numerical codes for modeling of flows in gas centrifuge
(2015) Bogovalov, S. V.; Borisevich, V. D; Borman, V. D.; Kislov, V. A.; Tronin, I. V.; Tronin, V. N.; Тронин, Иван Владимирович; Боговалов, Сергей Владимирович; Борисевич, Валентин Дмитриевич
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Damping of sound waves in strong centrifugal field
(2015) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V.; Тронин, Иван Владимирович; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович
A method for numerical calculation of the sound wave damping and dispersion law in a strong centrifugal field of the order of 106 g is considered. The damping is defined from the width of the resonance peak for different wave vectors. In the strong centrifugal field damping of the sound waves essentially exceeds the damping in the quiescent gas. © 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.
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Novel approach to the formation of the engineering skills of students
(2016) Sysoev, A. A.; Весна, Елена Борисовна
Только метаданные
Impact of the pulsed braking force on the axial circulation in a gas centrifuge
(2016) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V
Impact of the pulsed braking force on the axial gas circulation in centrifuges for a uranium isotope separation was investigated by the method of numerical simulation. Two camera model has been explored. The pulsed braking of the rotating gas results into generation of waves which propagate along all length of the rotor of the centrifuge. The wavelength appears in accordance with predictions of our analytic theory. Pulsations almost doubles the axial circulation flux in the working camera in comparison with the case of the steady state breaking force with the same average power. © 2015 Elsevier Inc. All rights reserved.
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Waves in a gas centrifuge
(2016) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V.; Тронин, Иван Владимирович; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович
Impact of the pulsed braking force on the axial gas circulation and gas content in centrifuges for uranium isotope separation was investigated by the method of numerical simulation. Pulsed brake of the rotating gas by the momentum source results into generation of the waves which propagate along the rotor of the centrifuge. The waves almost doubles the axial circulation flux in the working camera in compare with the case of the steady state breaking force with the same average power in the model under the consideration. Flux through the hole in the bottom baffle on 15% exceeds the flux in the stationary case for the same pressure and temperature in the model. We argue that the waves reduce the pressure in the GC on the same 15%.
Неизвестно
Impact of the waves on the product flux of the Iguasu gas centrifuge
(AIP Conference Proceeding, 2016) Bogovalov, S. V.; Kislov, V. A.; Tronin, I. V.; Тронин, Иван Владимирович; Боговалов, Сергей Владимирович; Кислов, Владимир Александрович
2D axisymmetric transient flow induced by a pulsed braking force in the Iguasu gas centrifuge is simulated numerically. The simulation is performed for two cases: transient and stationary. The braking forces averaged over the period of rotation are equal to each other in both cases. The transient case is compared with the stationary case where the flow is excited by the stationary braking force. In the transient case the gas flux through the gap in the bottom baffle exceeds on 15 % the same flux in the stationary case for the same gas content and temperature at the walls of the rotor. We argue that the waves can reduce the gas content in the GC on the same 15 %.
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Impact of waves on the circulation flow in the Iguasu gas centrifuge
(2017) Bogovalov, S.; Kislov, V.; Tronin, I.; Кислов, Владимир Александрович; Боговалов, Сергей Владимирович; Тронин, Иван Владимирович
Published under licence by IOP Publishing Ltd. 2D axisymmetric transient flow induced by a pulsed braking force in the Iguasu gas centrifuge (GC) is simulated numerically. The simulation is performed for two cases: transient and stationary. The braking forces averaged over the period of rotation are equal to each other in both cases. The transient case is compared with the stationary case where the flow is excited by the stationary braking force.Two models of the gas cenrifuge is simulated. There are two cameras in the first model and three cameras in the second one. In the transient case for the two cameras model pulsations almost doubles the axial circulation flux in the working camera. In the transient case for the three cameras model the gas flux through the gap in the bottom baffle exceeds on 15 % the same flux in the stationary case for the same gas content and temperature at the walls of the rotor. We argue that the waves can reduce the gas content in the GC on the same 15 %.
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Backlund transformations between four Lax-integrable 3D equations
(2017) Morozov, O. I.; Pavlov, M. V.
© 2017 the authors. Recently a classification of contactly-nonequivalent three-dimensional linearly degenerate equations of the second order was presented by E.V. Ferapontov and J. Moss. The equations are Lax-integrable. In our paper we prove that all these equations are connected with each other by appropriate Bäcklund transformations.