We have combined the velocity map imaging technique with time-of-flight measurements to study the surface photochemistry of KBr single crystals. This approach yields 3-dimensional velocity distributions of Br atoms resulting from 193 nm photodesorption. The velocity distributions indicate that at least two non-thermal mechanisms contribute to the photodesorption dynamics. Our experimental geome...

this work presents a numerical analysis of entropy generation in γ-shaped enclosure that was submitted to the natural convection process using a simple thermal lattice boltzmann method (tlbm) with the boussinesq approximation.  a 2d thermal lattice boltzmann method with 9 velocities, d2q9, is used to solve the thermal flow problem. the simulations are performed at a constant prandtl number (pr ...

A numerical investigation of entropy generation in laminar forced convection of gas flow over a backward facing step in a horizontal duct under bleeding condition is presented. For calculation of entropy generation from the second law of thermodynamics in a forced convection flow, the velocity and temperature distributions are primary needed. For this purpose, the three-dimensional Cartesian co...

The aerothermodynamics of spacecraft entering a planetary atmosphere are sensitive to the level of gas-surface accommodation governed by the gas-surface interaction. The modeling of this interaction plays an integral role in the solid surface boundary condition of the Direct Simulation Monte Carlo (DSMC) method. The Maxwell, and Cercignani, Lampis and Lord (CLL) gas-surface interaction models a...

We present a method for recovering the distribution functions of edge-on thin axisymmetric disks directly from their observable kinematic properties. The most generally observable properties of such a stellar system are the line-of-sight velocity distributions of the stars at different projected radii along the galaxy. If the gravitational potential is known, then the general two-integral distr...

We evaluate numerically the velocity field distributions produced by a bounded, two-dimensional fluid model consisting of a collection of parallel ideal line vortices. We sample at many spatial points inside a rigid circular boundary. We focus on "nearest-neighbor" contributions that result from vortices that fall (randomly) very close to the spatial points where the velocity is being sampled. ...