Experimental and numerical study of quasi-two-dimensional flow around a square cylinder in a magnetic field environment

doi:10.7523/j.ucas.2026.021

Abstract

Abstract: This study combines experimental measurements and numerical simulations to systematically investigate the effects of Hartmann number (Ha) and Reynolds number (Re) on flow field structure and stability under conditions of a blockage ratio of 0.1 and a rectangular cylinder aspect ratio of 2.25, with 74≤Ha≤510 and 500≤Re≤1500. The experiment uses an electromagnetic pump to drive liquid metal and measures flow velocity through wall potential probe technology, focusing on the influence of inlet velocity and magnetic field strength on flow characteristics. The numerical simulation, based on a quasi-two-dimensional model under strong magnetic fields, analyzes the flow field characteristics under different conditions. The results show that the experimental and numerical results exhibit good agreement in the critical Reynolds number (Re_cr) and the Strouhal number (St). Under a fixed magnetic field, the vortex shedding frequency increases with the Reynolds number. During the downstream convection and diffusion process, the frequency of the unsteady fluctuations remains stable, while the amplitude of the dominant frequency gradually decays. Under a fixed Reynolds number, the vortex shedding frequency increases with increasing magnetic field strength, whereas the vortex kinetic energy decreases significantly.

Key words: axial magnetic field, flow around a body, electric potential probe, vortex shedding frequency

CLC Number:

O361.3

MA Ruixue, DONG Siyu, LV Ze, CHEN Long. Experimental and numerical study of quasi-two-dimensional flow around a square cylinder in a magnetic field environment[J]. Journal of University of Chinese Academy of Sciences, DOI: 10.7523/j.ucas.2026.021.

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