Heated vertical duct flow of liquid metal with and without expansion

Selective catalytic reduction (SCR) is widely used to remove nitrogen oxides (NOx) in the flue gas of coal-fired power plants. The accumulation of ash particles inside the SCR-deNOx facility will increase the risk of catalyst deactivation or even damage. This paper presents the numerical and experimental investigations on the particle dispersal approach for the SCR-deNOx facility of a 1000 MW coal-fired power plant. The accumulation of different-sized particles is evaluated based on computational fluid dynamics (CFD) simulations. To prevent particles from accumulation, an optimized triangular deflector is proposed and attempts are made to find out the optimal installing position of the deflector. For the π-type SCR-deNOx facilities, the particle accumulation predominantly occurred on one side of the catalysts’ entrance, which corresponds to the inner side of the wedge-shaped turning. It is indicated that particles larger than 8.8 × 10−2 mm are responsible for the significant accumulation. The triangular deflector is proved to be an effective way to reduce particle accumulation and is found most efficient when it is installed at the high-speed area of the vertical duct. Flow model test (FMT) is carried out to validate the dispersal effect for the particle with relatively large sizes and the optimal installing position of the triangular deflector.

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Numerical Simulation of MHD Rectangular Duct Flow with FCI Based on Magnetic Induction Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.452-453.344 ◽

2012 ◽

Vol 452-453 ◽

pp. 344-347

Author(s):

Tian Neng Xu ◽

Jie Mao ◽

Hua Chen Pan

Keyword(s):

Numerical Simulation ◽

Pressure Drop ◽

Liquid Metal ◽

Magnetic Induction ◽

Metal Flow ◽

Duct Flow ◽

Rectangular Duct ◽

Induction Method ◽

Pressure Equalization ◽

Liquid Metal Flow

In dual-coolant and self-cooled blanket concepts, the magnetohydrodynamic (MHD) pressure drop is a key point that should be considered. In order to reduce the high MHD drop, it requires an understanding of the liquid metal flow in rectangular duct with FCI. In this paper, two cases that have different pressure equalization slot widths were simulated based on MHD module of FLUENT. It is found that with different widths of pressure equalization slot, velocity distribution and pressure drop changes a lot.

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Experimental study of liquid metal heat transfer in a vertical duct affected by coplanar magnetic field: Upward flow

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2020.119746 ◽

2020 ◽

Vol 156 ◽

pp. 119746

Author(s):

Nikita Razuvanov ◽

Natalya Pyatnitskaya ◽

Peter Frick ◽

Ivan Belyaev ◽

Valentin Sviridov

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Experimental Study ◽

Liquid Metal ◽

Upward Flow ◽

Vertical Duct

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Laminar and transitional liquid metal duct flow near a magnetic point dipole

Journal of Fluid Mechanics ◽

10.1017/jfm.2013.491 ◽

2013 ◽

Vol 735 ◽

pp. 553-586 ◽

Cited By ~ 7

Author(s):

Saskia Tympel ◽

Thomas Boeck ◽

Jörg Schumacher

Keyword(s):

Liquid Metal ◽

Magnetic Dipole ◽

Stationary Flow ◽

Reynolds Numbers ◽

Streamwise Velocity ◽

Dipole Field ◽

Spanwise Direction ◽

Point Dipole ◽

Duct Flow ◽

Magnetic Dipole Field

AbstractThe flow transformation and the generation of vortex structures by a strong magnetic dipole field in a liquid metal duct flow is studied by means of three-dimensional direct numerical simulations. The dipole is considered as the paradigm for a magnetic obstacle which will deviate the streamlines due to Lorentz forces acting on the fluid elements. The duct is of square cross-section. The dipole is located above the top wall and is centred in spanwise direction. Our model uses the quasistatic approximation which is applicable in the limit of small magnetic Reynolds numbers. The analysis covers the stationary flow regime at small hydrodynamic Reynolds numbers $\mathit{Re}$ as well as the transitional time-dependent regime at higher values which may generate a turbulent flow in the wake of the magnetic obstacle. We present a systematic study of these two basic flow regimes and their dependence on $\mathit{Re}$ and on the Hartmann number $\mathit{Ha}$, a measure of the strength of the magnetic dipole field. Furthermore, three orientations of the dipole are compared: streamwise-, spanwise- and wall-normal-oriented dipole axes. The most efficient generation of turbulence at a fixed distance above the duct follows for the spanwise orientation, which is caused by a certain configuration of Hartmann layers and reversed flow at the top plate. The enstrophy in the turbulent wake grows linearly with $\mathit{Ha}$ which is connected with a dominance of the wall-normal derivative of the streamwise velocity.

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