The Direct Simulation Monte Carlo (DSMC) method is used to simulate the flow of rarefied gases. In the Macroscopic Chemistry Method (MCM) for DSMC, chemical reaction rates calculated from local macroscopic flow properties are enforced in each cell. Unlike the standard total collision energy (TCE) chemistry model for DSMC, the new method is not restricted to an Arrhenius form of the reaction rat...

It is widely known that losses due to viscous, thermal and molecular relaxation play an important role in sound propagation. Traditionally, acoustics is concerned with the treatment of the fluid as a (linear) continuum using macroscopic quantities such as velocity and pressure as dependent variables. However, the continuum model has its limitations and the model breaks down for Knudsen numbers ...

The Direct Simulation Monte Carlo (DSMC) method was used to study the evaporation / condensation of iodine evaporating between parallel circular plates. The numerical 1D and 2D solutions are compared to the experimental result obtained by Mager et al.

In this paper, a Dynamic Sliding Mode Controller (DSMC) is proposed for trajectory tracking control of a nonholonomic Wheeled Mobile Robot (WMR) in which the centroid doesn't coincide to the connection center of driving wheels. This robust controller is designed based on the developed dynamical model of WMR in Cartesian coordinates, therefore, the application limits in polar coordinates is remo...

We present an efficient particle method for solving the Boltzmann equation. The key ingredients of this work are the variance reduction ideas presented in Baker and Hadjiconstantinou [L.L. Baker, N.G. Hadjiconstantinou, Variance reduction for Monte Carlo solutions of the Boltzmann Equation, Physics of Fluids, 17 (2005) (art. no, 051703)] and a new collision integral formulation which allows the...

In this thesis we investigate the ability of the Runge-Kutta Discontinuous Galerkin (RKDG) method to provide accurate and efficient solutions of the Boltzmann equation. Solutions of the Boltzmann equation are desirable in connection to small scale science and technology because when characteristic flow length scales become of the order of, or smaller than, the molecular mean free path, the Navi...

In the present investigation, slip-continuum and molecular (DSMC) flow models have been used to compare the drag coefficient on a confined microsphere over a range of Knudsen numbers between 0.01 and 0.4. The simulations consider a fixed Reynolds number (Re=0.125) and a range of blockage ratios from 2.0 up to 13.0. Two separate problem formulations have been studied; the first considers flow pa...