NUMERICAL STUDY OF WEDGE FLOW IN RAREFIED GAS FLOW REGIME USING A SLIP BOUNDARY CONDITION

In this paper, we propose a new slip boundary condition in hypersonic gas flow simulations. It is derived by considering the Langmuir isotherm adsorption into the Kaniadarkis et al. model of the kinetic theory of gas. Moreover, the motion of the adsorbed molecules over the surface (i.e. surface diffusion) is considered for the calculation of the mean free path in new slip condition. Three aerodynamic configurations are selected for evaluating new slip condition such as (1) the sharp-leading-edge flat plate, (2) circular cylinder in cross-flow, and (3) the sharp 25°–55° biconic cases. Hypersonic gas flows have the Mach number ranging from 6.1 to 15.6, and the working gases are argon and nitrogen. The simulation results show that new slip condition predicts better slip velocity than the Maxwell slip condition and gives good agreement with the direct simulation Monte-Carlo data for all cases considered in the present work.

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Rarefied gas flow between parallel plates

Mathematical Proceedings of the Cambridge Philosophical Society ◽

10.1017/s0305004100044844 ◽

1969 ◽

Vol 66 (1) ◽

pp. 189-196 ◽

Cited By ~ 3

Author(s):

M. M. R. Williams

Keyword(s):

Boundary Condition ◽

Integral Equation ◽

Gas Flow ◽

Rarefied Gas ◽

Volumetric Flow Rate ◽

Slip Boundary Condition ◽

General Boundary Condition ◽

Boltzmann Transport ◽

Parallel Plates ◽

Slip Boundary

AbstractThe flow of a rarefied gas between parallel plates has been studied via the linearized Boltzmann transport equation. Using a general boundary condition, which includes an arbitrary ratio of specular to diffuse reflection from the wall, we have derived an integral equation for the mass flow velocity. The integral equation is solved by using a replication property of the kernel and application of the method of Muskelishvili.The total volumetric flow rate is obtained and a slip boundary condition is deduced for use with the hydrodynamic equations.Certain aspects of the eigenvalue spectrum associated with the Boltzmann equation are discussed.

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On the Rarefied Gas Flow in Pipes

Volume 6: 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C ◽

10.1115/detc2005-84914 ◽

2005 ◽

Author(s):

Vladan D. Djordjevic

Keyword(s):

Knudsen Number ◽

Gas Flow ◽

Rarefied Gas ◽

Natural Extension ◽

Slip Boundary Condition ◽

Molecular Flow ◽

Rarefied Gas Flow ◽

Number Range ◽

Average Value ◽

Linearized Boltzmann Equation

Rarefied gas flow in a pipe is treated in the paper by modeling the slip boundary condition by means of a fractional derivative. At that the order of the derivative is conveniently chosen to be a function of the average value of the Knudsen number so that the entire Knudsen number range, from continuum flow to free molecular flow, is covered. Very good agreement with the solutions of linearized Boltzmann equation is achieved. The paper represents a natural extension of the work of the same author on the rarefied micro channel flow, published earlier.

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Heat transfer effects on carbon nanotubes suspended nanofluid flow in a channel with non-parallel walls under the effect of velocity slip boundary condition: a numerical study

Neural Computing and Applications ◽

10.1007/s00521-015-2035-4 ◽

2015 ◽

Vol 28 (1) ◽

pp. 37-46 ◽

Cited By ~ 68

Author(s):

Umar Khan ◽

Naveed Ahmed ◽

Syed Tauseef Mohyud-Din

Keyword(s):

Heat Transfer ◽

Carbon Nanotubes ◽

Boundary Condition ◽

Numerical Study ◽

Velocity Slip ◽

Slip Boundary Condition ◽

Transfer Effects ◽

Nanofluid Flow ◽

Slip Boundary ◽

Heat Transfer Effects

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DSMC simulation of rarefied gas flow over a 2D backward-facing step in the transitional flow regime: Effect of Mach number and wall temperature

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410020959872 ◽

2020 ◽

pp. 095441002095987

Author(s):

Deepak Nabapure ◽

Ram Chandra Murthy K

Keyword(s):

Mach Number ◽

Flow Regime ◽

Surface Properties ◽

Wall Temperature ◽

Gas Flow ◽

Rarefied Gas ◽

Transitional Flow ◽

Flow Properties ◽

Rarefied Gas Flow ◽

Backward Facing Step

Rarefied gas flow over a backward-facing step (BFS) is often encountered in separating flows prevalent in aerodynamic flows, engine flows, condensers, space vehicles, heat transfer systems, and microflows. Direct Simulation Monte Carlo (DSMC) is a powerful tool to investigate such flows. The purpose of this research is to assess the impact of Mach number and wall temperature on the flow and surface properties in the transitional flow regime. The Mach numbers considered are 5, 10, 25, 30, and the ratio of the temperature of the wall to that of freestream considered are 1, 2, 4, 8. The Reynolds number for the cases studied is 8.6, 17.2, 43, and 51.7, respectively. Typically the flow properties near the wall are found to increase with both Mach number and wall temperature owing to compressibility and viscous dissipation effects. The variation in flow properties is more sensitive to Mach number than the wall temperature. The surface properties are found to decrease with Mach number and increase with wall temperature. Moreover, in the wake of the step, the vortex’s recirculation length is reasonably independent of both free stream Mach number and wall temperature, whereas it decreases with Knudsen number.

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