We study the formation of disks via the cooling flow of gas within galactic haloes using smoothed particle hydrodynamics simulations. These simulations resolve mass scales of a few thousand solar masses in the gas component for the first time. Thermal instabilities result in the formation of numerous warm clouds that are pressure confined by the hot ambient halo gas. The clouds fall slowly onto...

Using the general theory developed by the author in the previous paper, the problems of thermophoresis and diffusio-phoresis have been examined with a view to elucidating the effect of a general gas-surface scattering law on the associated forces. It is found that, in thermo-phoresis, there exists a close coupling between the first anisotropic moment of the gas-surface scattering law and the so...

Two different hybrid particle-continuum methods are described for simulation of nonequilibrium gas and plasma dynamics. The first technique, used for nonequilibrium hypersonic gas flows, uses either a continuum description or a particle method throughout a flow domain based on local conditions. This technique is successful in reproducing the results of full particle simulations at a small fract...

The brilliance of a laser-produced soft X-ray source is enhanced for gaseous target concepts. In contrast to solid or liquid target materials, these sources are clean and versatile but provide a comparably low conversion efficiency of laser energy into EUV and soft X-ray radiation. The basic idea is to induce supersonic effects in the gas jet, leading to a local increase of the particle density...

In this paper we present a numerical scheme to simulate a moving rigid body with arbitrary shape suspended in a rarefied gas. The rarefied gas is simulated by solving the Boltzmann equation using a DSMC particle method. The motion of the rigid body is governed by the Newton-Euler equations, where the force and the torque on the rigid body is computed from the momentum transfer of the gas molecu...

In this paper, based on the BGK equation, Liouville's theorem, and symplecticity preserving property of a Hamiltonian flow, a well-balanced kinetic scheme for the compressible Navier-Stokes equations under external forcing field is developed. In order to construct such a scheme, the physical process of particles transport through a potential barrier at a cell interface will be modeled with pene...

This work presents a computational study of flow behaviour in a bubbling fluidized bed. The model is developed by using the commercial CFD code Fluent 6.3. The model is based on an Eulerian description of the gas and the particle phase. Different drag models are used and compared. The computational results are validated against experimental results. The experimental data are taken from Hulme (2...

The purpose of this study is to identify parameters influence on the particle deposition within fin and tube heat exchanger of air-conditioning systems by CFD analysis. First the basic sketch of periodic geometry drawn and meshing operation including boundary conditions was performed. Then the gas side properties and flow parameters were solved by ANSYS Fluent 14.5 software. Lagrangian equa...