In many industrial equipment such as boilers and heat exchangers, the cylindrical tubes are exposed to the gas- liquid two phase flow. For any immersed body in flow field vortex shedding is created with a frequency that may be constant or variable, according to conditions such as flow rates, geometry of body, and etc. The failure will happen in the equipment, when this frequency is close to...

In this article, a Ranque–Hilsch Vortex Tube has been optimized utilizing axial angles for nozzles. Effect of nozzles angles on the flow behavior has been investigated by computational fluid dynamics (CFD) techniques. A finite volume approach with the standard k–ε turbulence model has been used to carry out all the computations. The dimensions of studied vortex tubes are kept the same for all m...

In this paper, the behavior of shock wave discharged from the pipe end is studied. The shock wave is generated using the shock tube (MO-tube). The flow field while the shock moves downstream is visualized using shadow photography and schlieren photography. The propagation of shock wave and the phenomenon of the occurrence of second vortex ring are examined and discussed.

In order to decrease the fluid dynamic forces of the U-bent tube with a circular section and avoid the occurrence of fluid-structure interaction problems, three-dimensional simulations of fluid flows around the tubes are carried out. In the case that the axis of the curved tube with the circular section is prevented from being normal to the direction of the flows approaching the tube, the forma...

We perform a path-integral analysis of the string representation of the dual Abelian Higgs (DAH) model beyond the London limit, where the string describing the vortex of a flux tube has a finite thickness. We show that besides an additional vortex core contribution to the string tension, a modified Yukawa interaction appears as a boundary contribution in the type-II dual superconducting vacuum....

We investigate an electron in the plane interacting with the magnetic field due to an electric current forming a localized rotationally symmetric vortex. We show that independently of the vortex profile an electron with spin antiparallel to the magnetic field can be trapped if the vortex current is strong enough. In addition, the electron scattering on the vortex exhibits resonances for any spi...

Turbulent solar convection is a source of various processes observed as large-scale active phenomena, e.g., coronal mass ejections, formation of self-organized magnetic structures that appear on the surface as sunspots and pores, and other non-linear dynamical structures and phenomena. Modern realistic numerical simulations of solar turbulent phenomena are based on first physical principles and...

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