Cutting efficiency and quality are very sensitive to gas jet pressure and nozzle standoff distance. Do a high gas pressure and a small standoff distance necessarily give better material removal capability and cutting quality? Simple experiments to measure the mass flow rate were carried out for two types of geometry: a circular hole and a linear cut directly underneath an axisymmetric nozzle. T...

Numerical studies have been made of the mean thermal structure and of heat transfer by the axisymmetric regime of thermal convection in an annulus of liquid that rotates at .. rad/sec about a vertical axis and is subject to a horizontal temperature contrast dT C*. The non-linear time-dependent equations for axisymmetric flow have been integrated numerically on an I.B.M. 7094 computer for values...

We consider low-Reynolds-number axisymmetric flow about two spheres using a novel, biharmonic stream function. This enables us to calculate analytically not only the forces, but also the dipole moments stresslets and pressure moments and the associated resistance functions. In this paper the basics properties of axisymmetric flow and the stream function are discussed. Explicit series expansions...

Purpose – This paper aims to examine how using lattice Boltzmann method (LBM) aids the study of the isothermal-gas flow with slight rarefaction in long microtubes. Design/methodology/approach – A revised axisymmetric lattice Boltzmann model is proposed to simulate the flow in microtubes. The wall boundary condition combining the bounce-back and specular-reflection schemes is used to capture the...

Under a common potential, a finite mixture of ellipsoidal velocity distributions satisfying the Boltzmann collisionless equation provides a set of integrability conditions that may constrain the population kinematics. They are referred to as conditions of consistency and were discussed in a previous paper on mixtures of axisymmetric populations. As a corollary, these conditions are now extended...

The problem of three-dimensional potential flow past a thin rigid screen is reduced to a hypersingular boundary integral equation. This equation is then projected onto a flat reference screen, which is taken to be a circular disc. Solutions are obtained for screens that are axisymmetric perturbations from the disc, so that the screen is rippled concentrically. The added mass is calculated for a...

The Boussinesq equations for Rayleigh–Bénard convection are simulated for a cylindrical container with an aspect ratio near 1.5. The transition from an axisymmetric stationary flow to timedependent flows is studied using nonlinear simulations, linear stability analysis and bifurcation theory. At a Rayleigh number near 25000, the axisymmetric flow becomes unstable to standing or travelling azimu...

The Boussinesq equations for Rayleigh–Bénard convection are simulated for a cylindrical container with an aspect ratio near 1.5. The transition from an axisymmetric stationary flow to time-dependent flows is studied using nonlinear simulations, linear stability analysis and bifurcation theory. At a Rayleigh number near 25 000, the axisymmetric flow becomes unstable to standing or travelling azi...

Linearly unstable high b tokamak equilibria are shown to be nonlinearly stabilized by an axisymmetric flow containing both toroidal and poloidal components. As fingers of hot plasma produced by pressure driven ballooning instabilities start to convect out towards the bounding wall, an axisymmetric flow is self-consistently generated and opposes the growth of the fingers, maintaining confinement...

Abstract We review the surface flux transport model for evolution of magnetic patterns on Sun’s surface. Our underlying motivation is to understand model’s prediction polar field (or axial dipole) strength at end solar cycle. The main focus “classical” model: namely, steady axisymmetric profiles differential rotation and meridional flow, uniform supergranular diffusion. Nevertheless, concentrat...