Stability of flowing PbLi alloy between coaxial cylinders under magnetic field

Brahim Mahfoud

doi:10.57056/ajet.v8i2.150

Authors

Brahim Mahfoud Department of Mechanical, University of MOB-Bouira, Bouira, 10000, Algeria.

DOI:

https://doi.org/10.57056/ajet.v8i2.150

Keywords:

Coaxial cylinders, Magnetic field, PbLi alloy, Vortex breakdown, Stability

Abstract

In this research, numerical simulations were performed to investigate the stability of a flowing PbLi alloy (Pr = 0.032) within two coaxial vertical cylinders, while subjected to an axial magnetic field. The primary objective of this study was to analyze how the presence of the axial magnetic field affected both vortex breakdown and swirling flow phenomena. To achieve this, the governing equations, which included the Navier-Stokes equations and potential equations, were solved using the finite-volume method. The numerical simulations presented results for three aspect ratios (A= 1.5, 2.0, and 2.5) and three annuli (R = 0.9, 0.8, and 0.7). In the hydrodynamic scenario, vortex breakdown was observed close to the inner cylinder as a result of the intensified pumping effect caused by the Ekman boundary layer. The findings demonstrated that the onset of oscillatory instability was initiated by increasing the Reynolds number to a critical value. However, when a magnetic field is intensified, the vortex breakdown vanishes, and its limits will shrink. Stability diagrams were created to depict the boundaries within which a vortex breakdown bubble emerges, allowing for a visual picture of its occurrence.

References

Jun J, Unocic K.A , Lance MJ , Meyer HM , Pint BA. Compatibility of FeCrAlMo with flowing PbLi at 500°-650 °C. Journal of Nuclear Materials,2020, 528: 151847, https://doi.org/10.1016/j.jnucmat.2019.151847

Jiang Z, Zheng M, Jiang M, Xin J. The influence of crystal orientation on corrosion behavior of iron in liquid PbLi Wenyi Ding. Journal of Nuclear Materials, 2018, 509 : 212-217, https://doi.org/10.1016/j.jnucmat.2018.06.039

Zinkle J, Terrani KA , Snead LL . Motivation for utilizing new high-performance advanced. materials in nuclear energy systems, Current Opinion in Solid State and Materials Science, 2016, 20: 401-410, https://doi.org/10.1016/j.cossms.2016.10.004

Edemetti F, Piazza I.Di , Del Nevo A . Caruso G. Thermal-hydraulic analysis of the DEMO WCLL elementary cell: BZ tubes layout optimization, Fusion Engineering and Design,2020,160: 111956, https://doi.org/10.1016/j.fusengdes.2020.111956

Gonzalez M , Garcia JM , Kravalis K . Chemical compatibility of bulk alumina in flowing PbLi alloy under magnetic field, Fusion Engineering and Design, 2021,170: 112704 doi. /10.1016/j.fusengdes.2021.112704

Mahfoud B. Effects of an Axial Magnetic Field on Vortex Breakdown and Fluid Layer, Journal of Applied Fluid Mechanics ,2021, 14: 1741–1753, https://doi.org/10.47176/jafm.14.06.32585

Smolentsev S, Li FC , Morley N , Ueki Y, Abdou M , Sketchley T. Construction and initial operation of MHD PbLi facility at UCLA, Fusion Engineering and Design, 2013, 88: 317-326 https://doi.org/10.1016/j.fusengdes.2013.03.018

Smolentsev S, Saedi S, Malang S, Abdou M. Numerical study of corrosion of ferritic/martensitic steels in the flowing PbLi with and without a magnetic field, Journal of nuclear materials, 2013, 432: 294-304 https://doi.org/10.1016/j.jnucmat.2012.08.027

Li FC, Sutevski D, Smolentsev S, Abdou M. Experimental and numerical studies of pressure drop in PbLi flows in a circular duct under non-uniform transverse magnetic field, Fusion Engineering and Design, 2013, 88 : 3060-3071, https://doi.org/10.1016/j.fusengdes.2013.08.006

Smolentsev S, Li FC, Morley N, Ueki Y, Abdou M . Construction and initial operation of MHD PbLi facility at UCLA, Fusion Engineering and Design, 2013, 88 : 317-326, https://doi.org/10.1016/j.fusengdes.2013.03.018

Mistrangelo C, Bühler L. Magnetohydrodynamic flows in liquid metal blankets for fusion reactors, PAMM • Proc. Appl. Math. Mech 2017, 17: 115 – 118, https://doi.org/10.1002/pamm.201710033

Mahfoud B. Magnetohydrodynamic effect on vortex breakdown zones in coaxial cylinders, European Journal of Mechanics-B/Fluid, 2021, 89: 445–457. doi.org/10.1016/j.euromechflu.2021.07.007 0997-7546

Benhacine H, Mahfoud B., Salmi M. Stability of an Electrically Conducting Fluid Flow between Coaxial Cylinders under Magnetic field.” Journal of Applied Fluid Mechanics, 2022, 15 : 1741-1753, DOI: 10.47176/JAFM.15.02.33050

Mahfoud B, Laouari A, Hadjadj A, Benhacine H. Counter-rotating flow in coaxial cylinders under an axial magnetic field. European Journal of Mechanics-B/Fluids, 2019; 78: 139-146. doi.org/10.1016/j.euromechflu.2019.06.009

Mahfoud B., Benhacine H., Laouari A., Bendjaghlouli A. Magnetohydrodynamic Effect on Flow Structures Between Coaxial Cylinders Heated from Below, Journal of Thermophysics and Heat Transfer, 2019, 34(2): 1-10. https://doi.org/10.2514/1.T5805.

Escudier M. Observations of the flow produced in a cylindrical container by a rotating endwall, Experiments in Fluids, 1984, 2: 189–196.