Decay of honeycomb-generated turbulence in a duct with a static transverse magnetic field is studied via direct numerical simulations. The simulations follow the revealing experimental study of Sukoriansky et al. ( Exp. Fluids , vol. 4 (1), 1986, pp. 11–16), in particular the paradoxical observation of high-amplitude velocity fluctuations, which exist in the downstream portion of the flow when the strong transverse magnetic field is imposed in the entire duct including the honeycomb exit, but not in other configurations. It is shown that the fluctuations are caused by the large-scale quasi-two-dimensional structures forming in the flow at the initial stages of the decay and surviving the magnetic suppression. Statistical turbulence properties, such as the energy decay curves, two-point correlations and typical length scales are computed. The study demonstrates that turbulence decay in the presence of a magnetic field is a complex phenomenon critically depending on the state of the flow at the moment the field is introduced.
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Liquid metal swirling flow affected by transverse magnetic field
In this work we study numerically liquid metal flow in a square duct under the influence of
a transverse magnetic field applied in a spanwise direction (coplanar). The key interest of the
present study is an attempt of passive control of flow regimes developed under magnetic field and thermal loads by applying specially shaped conditions, such as swirling, at the duct inlet.
In this paper, we report results of numerical simulations of the interaction of swirling flow and
transverse magnetic field in a square duct flow. Analysis of the obtained regimes might be
important for the development of an experimental setup, in order to design corresponding inlet
sections.
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- Award ID(s):
- 1803730
- NSF-PAR ID:
- 10282587
- Date Published:
- Journal Name:
- Magnetohydrodynamics
- Volume:
- 56
- Issue:
- 2-3
- ISSN:
- 0024-998X
- Page Range / eLocation ID:
- 121 to 130
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Decay of honeycomb-generated turbulence in a duct with a static transverse magnetic field is studied via high-resolution direct numerical simulations. The simulations follow the experimental study [1], in particular the paradoxical observation of high-amplitude velocity fluctuations, which exist in the downstream portion of the flow when the strong transverse magnetic field is imposed in the entire duct including the honeycomb exit, but not in other configurations. It is shown that the fluctuations are caused by the large-scale quasi- two-dimensional structures forming in the flow at the initial stages of the decay and surviving the magnetic suppression. The study demonstrates that turbulence decay in the presence of a magnetic field is a complex phenomenon critically depending on the state of the flow at the moment the field is introduced.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.22364/mhd.56.2-3.3
