We consider the dynamics of axial velocity and of scalar transport in the stretched-spiral vortex model of turbulent fine scales. A large-time asymptotic solution to the scalar advection-diffusion equation, with an azimuthal swirling velocity field provided by the stretched spiral vortex, is used together with appropriate stretching transformations to determine the evolution of both the axial v...

A compensation method is proposed by which the uniformly shielded area of the axial magnetic field in a relatively short, open-structure axial magnetic shield can be extended. An open-ended cylindrical magnetic shield of 120 cm in length, 52 cm inner diameter, and a ;0.5 mm total thickness of the shielding material is used to demonstrate the idea. The shield axis is oriented along the horizonta...

A number of attempts have been made to study heat flow in circular cross-section of human limbs. But almost no attempt has been reported in literature about study of heat flow in the tissue layers of elliptical shaped human limbs. Therefore, a seminumerical model has been developed to study heat flow in peripheral layers of three-dimensional elliptical shaped human limbs for a steady state case...

The present study is carried out to investigate the magneto-viscous effects on incompressible ferrofluid flow over a porous rotating disc with suction or injection on the surface of the disc subjected to a magnetic field. The flow under consideration is axi-symmetric steady ferrofluid flow of electrically non-conducting fluid. Karman’s transformation is used to convert the governing boundary la...

In this paper we report experimental results on the granular temperature and velocity profile of glass beads in steady-state flow inside a flat-bottomed silo. We found that dynamics system during discharge is stable mesoscopic scale. particular, ordered directional movement particles can occur near orifice. addition, correlation between distribution vector field opposite radial axial directions...

Pressure distributions over a 20° conical forebody are computed by the commercial CFD software ANSYS CFX. Free stream velocity is 30 m/s, Reynolds number based on the forebody base diameter is 0.3×10 6 , and the angle of attack ranges from 10° to 35°. The C-O structural grids are used to compute the entire flow field. The governing equations are steady Reynolds-Averaged Navier-Stokes Equations ...

One challenge for the numerical simulation of a dry scroll vacuum pump is the discretization of the chamber volume, which changes with time. In addition, the flow characteristics are very complex including the leakage flow caused by radial and axial gaps between the rotors and the housing. For engineers and designers it is imperative to understand the influence of such leakage flows on the effi...

Theoretical and numerical analysis is performed for an inviscid axisymmetric vortical bathtubtype flow. The level of vorticity is kept high so that the image of the flow on the radial-axial plane (r-z plane) is not potential. The most significant findings are: 1) the region of validity of the strong vortex approximation is separated from the drain by a buffer region; 2) the powerlaw asymptote o...