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In this paper, we present a numerical investigation into the influence of electric and magnetic fields on the dynamics of a suspended liquid film that carries an electric current. A nonuniform magnetic field is considered utilizing a disk-shaped magnet located above the two-dimensional fluid. Electric and magnetic forces exerted on the fluid induce a new dynamical features. We perform a numerical study of the dynamics of such two-dimensional fluid system commonly named Liquid Film Motor. The presence of the nonuniform external magnetic field causes changes in the fluid’s behavior. Specifically, the previously symmetric vortex becomes asymmetric under the influence of the magnetic field. In this dynamic behavior, as the external magnetic field increases, the center of the vortex shifts in a direction perpendicular to the electric current passing through the fluid film. The unique combination of electric and magnetic field allows to manipulate the motion of the vortex without resorting to traditional mechanical methods. This finding implies that the motion of the vortex can be directed and controlled by adjusting the strength of the external magnetic field, without the need for direct contact with the fluid or mechanical tools. [ABSTRACT FROM AUTHOR]

Unsteady cavitating turbulent flow around a NACA66 hydrofoil was simulated using a mass transfer cavitation model and a modified filter-based turbulence model in this paper. The modified filter-based turbulence model can accurately predict the pressure coefficient in midplane and shedding frequency of the unsteady cloud cavitation than standard κ – 𝜀 model and filter-based turbulence model. The time evolution of transient cavitation cloud structure predicted by the three-turbulence model was compared. The result which was predicted by the modified filter-based turbulence model is in good agreement with the experimental results. The time evolution of re-entrant jet had been analyzed. The instantaneous wall-pressure evolution on the suction surface (SS) predicted by the modified filter-based turbulence model had been analyzed. The cavitation-vortex interaction had been analyzed in this study. The different effects on the cavitation-vortex interaction of the vortex stretching term, vortex dilatation term and baroclinic torque term in the transport equation of vorticity had been discussed. [ABSTRACT FROM AUTHOR]

Vortexes induced by tsunamis, “tsunami vortexes”, pose a potential danger for ship evacuation, and their prediction is important to determine their role in navigation and safe vessel evacuation. This study simulated tsunami-induced vortexes in Osaka Bay and investigated their spatial and temporal scales using a port-resolved, high-resolution tsunami model based on a scenario for the largest tsunamigenic earthquake expected to occur along the Nankai Trough in the near future. Vortexes induced by tidal currents were also evaluated using a realistic tidal simulation for comparison with the magnitudes of the tsunami vortexes. The tsunami simulation identified the dominant areas of the tsunami vortexes characterized by the magnitude of the vorticity. Unified maps of tsunami speeds and vortexes showed the difficult areas for ship evacuation and indicated that these areas can persist after the approach of the leading wave around the entrances to port areas. The areas of tsunami vortex formation were largely deduced by analyzing the vorticity fields in the tidal simulations, because the magnitude of tsunami-induced vorticities was closely correlated with that of the tide-induced vorticities. The combination of tide and tsunami simulations can identify areas of tsunami vortex formation and provide valuable information to guide measures for safer vessel evacuation. [ABSTRACT FROM AUTHOR]

In this paper, starting from Biot-Savart mechanics for entangled vortex-membranes, a new theory - knot physics - is developed to explore the underlying physics of quantum mechanics. Owning to the conservation conditions of the volume of knots on vortices in incompressible fluid, the shape of knots will never be changed and the corresponding Kelvin waves cannot evolve smoothly. Instead, the knot can only be split. The knot-pieces evolve following the equation of motion of Biot-Savart equation that becomes Schrödinger equation for probability waves of knots. The classical functions for Kelvin waves become wave-functions for knots. The effective theory of perturbative entangled vortex-membranes becomes a traditional model of relativistic quantum field theory - a massive Dirac model. As a result, this work would help researchers to understand the mystery in quantum mechanics. [ABSTRACT FROM AUTHOR]