Two phenomena can produce chattering: switching of input control signal and the large amplitude of this switching (switching gain). To remove the switching of input control signal, dynamic sliding mode control (DSMC) is used. In DSMC switching is removed due to the integrator which is placed before the plant. However, in DSMC the augmented system (system plus the integrator) is one dimension bi...

A new approach to DSMC collision modelling, called viscosity-DSMC or μ-DSMC, is described in which the time-averaged temperature is used to set the characteristic collision cross-section in each cell such that the Chapman-Enskog viscosity is that given by any desired viscosity law μ = μ (T ), including a curve fit to experimental data. For example, a hard sphere collision model, with hard spher...

Abstract. Comparison of particle (DSMC) simulation with the numerical solution of the Navier-Stokes (NS) equations for pressure-driven plane Poiseuille flow is presented and contrasted with that of the acceleration-driven Poiseuille flow. Although for the acceleration-driven case DSMC measurements are qualitatively different from the NS solution at relatively low Knudsen number, the two are in ...

Keywords: DSMC IP Molecular diffusion Time step Cell size a b s t r a c t The direct simulation Monte Carlo (DSMC) method is a powerful particle-based method for modeling gas flows. It works well for relatively large Knudsen (Kn) numbers, typically larger than 0.01, but quickly becomes computationally intensive as Kn decreases due to its time step and cell size limitations. An alternative appro...

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A hybrid particle scheme is presented for the simulation of compressible gas flows involving both continuum regions and rarefied regions with strong translational nonequilibrium. The direct simulation Monte Carlo (DSMC) method is applied in rarefied regions, while remaining portions of the flowfield are simulated using a DSMC-based low diffusion particle method for inviscid flow simulation. The...

The Direct Simulation Monte Carlo (DSMC) Method is the most suitable method for the simulation of rareeed and micro-scale gas ows. The method has been used in a wide range of applications incorporating complex geometries and thermodynamical-chemical non-equilibrium. The method is however, computationally intensive and its application to more complex and dense problems is hampered by current ser...

Airflow over a flat plate at zero incidence is investigated as a function of the Reynolds number Re and the Mach number M under subsonic, low-Reynolds-number conditions. The flows are simulated using the direct simulation Monte Carlo (DSMC) method and the information preservation (IP) method that is a modified DSMC method developed for low-speed rarefied gas flows. Good agreement is obtained be...

A hybrid particle scheme, which is based on the direct simulation Monte Carlo (DSMC) method and incorporates a low diffusion particle method for continuum flow simulation, is extended for improved efficiency and wider applicability. The hybrid scheme is intended for simulation of gas flows involving a wide range of Knudsen number regimes, where strong coupling is desired between calculations in...

Alexander, Garcia and Alder [1] introduced the Consistent Boltzmann Algorithm (CBA) as a simple variant of Direct Simulation Monte Carlo (DSMC) for dense gases. In CBA, collisions alter both the positions and velocities of the particles. In the present work the limiting kinetic equation for CBA is derived; the formulation is similar to the proof that the Boltzmann equation is the limiting kinet...