Authors & Affiliations
Belyaev I.A.1,2, Razuvanov N.G.1, Krasnov D.S.3, Sviridov V.G.1,2
1 Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow, Russia
2 National Research University "Moscow Power Engineering Institute", Moscow, Russia
3 Technical University Ilmenau, Ilmenau, Germany
Razuvanov N.G. – Leading Researcher, Dr. Sci. (Techn.), Joint Institute for High Temperatures of Russian Academy of Science.
Krasnov D.S. – Senior Researcher, Cand. Sci. (Phys.-Math.), Technical University Ilmenau.
Sviridov V.G. – Head of Department, Dr. Sci. (Techn.), Professor, Joint Institute for High Temperatures of the Russian Academy of Sciences, National Research University "Moscow Power Engineering Institute".
The article presents data summarizing experimental studies of the liquid metal downflow in a duct under the influence of a transverse magnetic field applied along the long side of the duct. The configuration under consideration is close to the conditions of the blanket module of a tokamak-type thermonuclear reactor. Mercury is used as a model liquid metal. Experiments are conducted using immersion probe with microthermcouple moving inside the duct at certain cross section, which then point by point restores profiles of averaged and fluctuating temperature.
The combined effect of electromagnetic forces and buoyancy forces leads to the formation of secondary vortices in the flow with respect to the main flow, which cause fluctuation of temperature with high amplitude and low. The paper analyzes the temperature signals accompanying the pulsating flow of liquid metal under the influence of a strong transverse magnetic field and a significant thermal load. Different configurations of the applied thermal load, namely symmetric and asymmetric heating, generate different in structure and statistical characteristics, but common in its nature phenomena. During symmetric heat load quasiharmomic temperature fluctuations have been observed. During asymmetric heat load periodic peaks of temperature have been observed. For formal distinction of types of the observed flows it is offered to use coefficient of harmonic distortions.
In this paper, we have experimentally studied the temperature signals formed in strong magnetic field, analyzed their statistical characteristics, measured the scale of emerging structures, determined the characteristic flow regimes, and proposed terminology to describe the different types of observed temperature fluctuations.
liquid metal, mercury, magnetohydrodynamics (MHD), heat transfer, probe measuring, mixed convection, duct flows
1. Rachkov V.I., Sorokin A.P., Zhukov A.V. Teplogidravlicheskie issledovaniya zhidkometallicheskikh teplonositeley v yadernykh energeticheskikh ustanovkakh [Thermal hydraulic studies of liquid-metal coolants in nuclear-power facilities]. Teplofizika vysokikh temperatur - High Temperature, 2018, vol. 56, no. 1, pp. 124—137.
2. Wong C.P.C. et al. Overview of liquid metal TBM concepts and programs. Fusion Engineering and Design, 2008, vol. 83, no. 7, pp. 850—857.
3. Zmitko M. et al. The European ITER test blanket modules: Progress in development of fabrication technologies towards standardization. Fusion Engineering and Design, 2016, vol. 109, pp. 1687—1691.
4. Kovalenko V.G. et al. Progress in design development and research activity on LLCB TBM in Russian Federation. Fusion Engineering and Design, 2016, vol. 109, pp. 521—531.
5. Aiello G. et al. Development of the helium cooled lithium lead blanket for DEMO. Fusion Engineering and Design, 2014, vol. 89, no. 7. pp. 1444—1450.
6. Smolentsev S. et al. Dual-coolant lead-lithium (DCLL) blanket status and R&D needs. Fusion Engineering and Design, 2015, vol. 100, pp. 44—54.
7. Belyaev I.A. et al. Features of MHD heat transfer in simple channels. Magnetohydrodynamics, 2018, vol. 54, no. 3, pp. 245—259.
8. Belyaev I.A., Poddubnyi I.I., Razuvanov N.G., Sviridov V.G. Otsenka vliyaniya pul'satsiy temperatury na konstruktsiyu zhidkometallicheskogo modulya reaktora-tokamaka [Evaluation of temperature fluctuations influence on the structure of tokamak-reactor liquid metal blanket module]. Voprosy Atomnoy Nauki i Tekhniki. Seriya: Termoyadernyy sintez - Problems of Atomic Science and Technology. Series: Thermonuclear fusion, 2018, vol. 41, no. 1, pp. 41—52.
9. Poddubny I.I. Issledovanie gidrodinamiki i teploobmena zhidkogo metalla primenitel'no k usloviyam termoyadernogo reaktora. Diss. kand. tekhn. nauk [Investigation of hydrodynamics and heat transfer of liquid metal in relation to the conditions of a thermonuclear reactor. Cand. techn. sci. diss.]. Moscow, MPEI, 2016.
10. Poddubnyi I.I. et al. Investigation of heat transfer in liquid-metal flows under fusion-reactor conditions. Physics of Atomic Nuclei, 2016, vol. 79, no. 7, pp. 1170—1180.
11. Kostychev P.V., Poddubnyi I.I., Pyatnickaya N.Yu., Razuvanov N.G., Sviridov E.V. Osobennosti teploobmena pri techenii zhidkogo metalla v vertikal'nom kanale v komplanarnom magnitnom pole [Peculiarity of the heat transfer of liquid metal downward flow in vertical duct in coplanar magnetic field]. Voprosy Atomnoy Nauki i Tekhniki. Seriya: Termoyadernyy sintez - Problems of Atomic Science and Technology. Series: Thermonuclear fusion, 2017, vol. 40, no. 3, pp. 68—77.
12. Zikanov O., Listratov Y.I., Sviridov V.G. Natural convection in horizontal pipe flow with a strong transverse magnetic field. Journal of Fluid Mechanics, 2013, vol. 720, pp. 486—516.
13. Belyaev I.A., Razuvanov N.G., Sviridov V.G. etod rascheta smeshannoy MGD-konvektsii v vertikal'nom kanale [Method of MHD mixed-convection calculation in a vertical duct]. Teplofizika vysokikh temperatur - High Temperature, 2018. (unpublished).