Comment on ‘‘Simulation of a two-dimensional Rayleigh-Bénard system using the direct simulation Monte Carlo method’’

The direct simulation Monte Carlo method is applied in this paper to simulate the micro Rayleigh-Bénard convection for the Rayleigh number of 10,159 and the Knudsen number of 0.01 in a time-dependent manner. A monatomic gas is enclosed between two infinite, parallel plates with the bottom plate at a higher temperature. Cases of three different computational domain sizes in the horizontal directions are simulated. Evolutions of the convective flow unsteady disturbances patterns and the wall heat transfer are studied in detail. Three stages of distinct flow characteristics can be identified as the flows develop from an initially uniform state. In the first stage, the heat is transferred mainly by conduction. The onset of the vortical flow structures marks the beginning of the second stage. Significant differences in the flow and the heat transfer characteristics are observed in the third stage of the three simulated flows. It is found that the simulated microflows develop vortex rolls that advect along the plates at uniform speeds, which has not been reported previously.

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Determining Aerothermodynamic Effects on Very-Low-Earth-Orbit Satellites Using Direct Simulation Monte Carlo Method

International Journal of Computational Fluid Dynamics ◽

10.1080/10618562.2021.1942458 ◽

2021 ◽

pp. 1-24

Author(s):

ChungChun Hsieh ◽

ChienYu Pan ◽

MingChung Lo

Keyword(s):

Monte Carlo ◽

Monte Carlo Method ◽

Direct Simulation Monte Carlo ◽

Low Earth Orbit ◽

Earth Orbit ◽

Direct Simulation ◽

Low Earth Orbit Satellites ◽

Simulation Monte Carlo

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Study on the Deposition Profile Characteristics in the Micron-Scale Trench Using Direct Simulation Monte Carlo Method

Journal of Fluids Engineering ◽

10.1115/1.2820648 ◽

1998 ◽

Vol 120 (2) ◽

pp. 296-302 ◽

Cited By ~ 5

Author(s):

Masato Ikegawa ◽

Jun’ichi Kobayashi ◽

Morihisa Maruko

Keyword(s):

Monte Carlo ◽

Monte Carlo Method ◽

Boundary Conditions ◽

Gas Flow ◽

Direct Simulation Monte Carlo ◽

Low Pressure ◽

Sputter Deposition ◽

Direct Simulation ◽

Simulation Monte Carlo ◽

Profile Characteristics

As integrated circuits are advancing toward smaller device features, step-coverage in submicron trenches and holes in thin film deposition are becoming of concern. Deposition consists of gas flow in the vapor phase and film growth in the solid phase. A deposition profile simulator using the direct simulation Monte Carlo method has been developed to investigate deposition profile characteristics on small trenches which have nearly the same dimension as the mean free path of molecules. This simulator can be applied to several deposition processes such as sputter deposition, and atmospheric- or low-pressure chemical vapor deposition. In the case of low-pressure processes such as sputter deposition, upstream boundary conditions of the trenches can be calculated by means of rarefied gas flow analysis in the reactor. The effects of upstream boundary conditions, molecular collisions, sticking coefficients, and surface migration on deposition profiles in the trenches were clarified.

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