Nonideal gas flow and heat transfer in micro- and nanochannels using the direct simulation Monte Carlo method

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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Computations of Low Pressure Fluid Flow and Heat Transfer in Ducts Using Direct Simulation Monte Carlo Method

10.1115/imece1999-1063 ◽

1999 ◽

Author(s):

Fang Yan ◽

Bakhtier Farouk

Keyword(s):

Heat Transfer ◽

Monte Carlo ◽

Noble Gas ◽

Direct Simulation Monte Carlo ◽

Low Pressure ◽

Direct Simulation ◽

Flow And Heat Transfer ◽

Gas Transport Properties ◽

Pressure Profiles ◽

Simulation Monte Carlo

Abstract High Knudsen (Kn) number flows are found in vacuum and micro-scale systems. Such flows are characterized by non-continuum behavior. For gases, the flows are usually in the slip or transition regimes. In this paper, the direct simulation Monte Carlo (DSMC) method has been applied to compute low pressure, high Kn flow fields in partially heated channels. Computations were carried out for nitrogen, argon, hydrogen, oxygen and noble gas mixtures. Variation of the Kn is obtained by reducing the pressure while keeping the channel width constant. Nonlinear pressure profiles along the channel centerline are observed. Heat transfer from the channel walls is also calculated and compared with the Graetz solution. The effects of varying pressure, inlet flow and gas transport properties (Kn, Reynolds number, Re and the Prandtl number, Pr respectively) on the wall heat transfer (Nu) were examined. A simplified correlation for predicting Nu¯ as a function of Pe¯ and Kn¯ is presented.

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Insights into flow and heat transfer aspects of hypersonic rarefied flow over a blunt body with aerospike using direct simulation Monte-Carlo approach

Aerospace Science and Technology ◽

10.1016/j.ast.2017.02.024 ◽

2017 ◽

Vol 66 ◽

pp. 119-128 ◽

Cited By ~ 16

Author(s):

Arun Kumar Chinnappan ◽

G. Malaikannan ◽

Rakesh Kumar

Keyword(s):

Heat Transfer ◽

Monte Carlo ◽

Blunt Body ◽

Direct Simulation Monte Carlo ◽

Direct Simulation ◽

Rarefied Flow ◽

Monte Carlo Approach ◽

Flow And Heat Transfer ◽

Simulation Monte Carlo

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Direct Simulation Monte Carlo Method for the Simulation of Rarefied Gas Flow in Discrete Track Recording Head/Disk Interfaces

Journal of Tribology ◽

10.1115/1.2991166 ◽

2008 ◽

Vol 131 (1) ◽

Cited By ~ 15

Author(s):

Maik Duwensee ◽

Frank E. Talke ◽

Shoji Suzuki ◽

Judy Lin ◽

David Wachenschwanz

Keyword(s):

Monte Carlo ◽

Monte Carlo Method ◽

Gas Flow ◽

Rarefied Gas ◽

Direct Simulation Monte Carlo ◽

Direct Simulation ◽

Rarefied Gas Flow ◽

Recording Head ◽

Discrete Track ◽

Simulation Monte Carlo

The direct simulation Monte Carlo method is used to study rarefied gas flow between an inclined plane slider bearing and a nanochannel representing one groove in discrete track recording head/disk interfaces. The forces acting on the slider are determined as a function of slider pitch angle, disk velocity, groove pitch, width, and groove depth. It is found that the influence of manufacturing tolerances on slider forces is smaller for deep and wide grooves than for the case of shallow and narrow grooves.

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Gas Properties Effects in Microchannel Studies Using Direct Simulation Monte Carlo

ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels: Parts A and B ◽

10.1115/fedsm-icnmm2010-31022 ◽

2010 ◽

Author(s):

Masoud Darbandi ◽

Abolfazl Karchani ◽

Hassan Akhlaghi ◽

Gerry Schneider

Keyword(s):

Heat Transfer ◽

Monte Carlo ◽

Slip Flow ◽

Direct Simulation Monte Carlo ◽

Direct Simulation ◽

Polyatomic Gases ◽

Flow And Heat Transfer ◽

Flow Through ◽

Simulation Monte Carlo ◽

Gas Properties

This paper concern is to study the gas properties effect in flow and heat transfer behaviors through microchannels using the direct simulation Monte Carlo method. The flow is rarefied and supersonic. The channels are investigated at two different inlet boundary conditions. The collision process is modeled using the NTC (no-time-counter) scheme. The VHS model is chosen to simulate collision between particle pairs. The study is provided for many different gases including nitrogen, helium, and oxygen. The Knudsen number is chosen in a manner to provide slip flow through the channel. The results show that the heat transfer from the wall is lower for heavier gases. A comparative study among the monatomic, diatomic, polyatomic gases shows that the heat transfer rate is lower for the polyatomic gases. The result shows that, the heat transfer from the wall is lower for the heavier gases than that for the lighter gas. For a fixed Mach number, the heat transfer from the wall decreases as the molecular diameter increases.

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