Knudsen number (Kn)
Calculation of Friction Coefficient and Analysis of Fluid Flow in a Stepped Micro-Channel for Wide Range of Knudsen Number Using Lattice Boltzmann (MRT) Method
... large number of discrete velocities are not numerically ...Kn number in slip flow ...of Knudsen number in slip and transition flow ...of Knudsen numbers that shows the regimes of flows ...
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Analysis of the thermomechanical inconsistency of some extended hydrodynamic models at high Knudsen number
... Equation (28) has a strong similarity, not only in its form but also in its derivation, to the (extended) Boltzmann kinetic equation that leads to the ‘ghost effect’ (i.e. where high Knudsen number terms are ...
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Modelling thermally induced non-equilibrium gas flows by coupling kinetic and extended thermodynamic methods
... In terms of the system entropy, it is very interesting to note that, unlike the other flow properties, the distributions of entropies are totally different between the lower and higher Knudsen numbers. We have ...
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Slip Effects on the Unsteady MHD Pulsatile Blood Flow through Porous Medium in an Artery under the Effect of Body Acceleration
... Hartmann number Ha, Knudsen number kn, Womersley parameter α, frequency of the body acceleration b, the permeability parameter of porous medium k and have been shown through Figures 2 to ...Hartmann ...
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Modeling of Knudsen layer effects in micro/nanoscale gas flows
... non-dimensional Knudsen number, Kn, defined as the ratio of the molecular mean free path (MFP) of the gas, λ, to a characteristic flow field dimension, indicates the flows are often ...a Knudsen ...
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Capturing Knudsen layer phenomena using lattice Boltzmann model
... encountered in micro- and nano-scale systems typically involve low Mach numbers and low Knudsen numbers. Under these conditions, the DSMC approach is not computationally efficient due to the requirement to perform ...
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Lattice Boltzmann modelling Knudsen layer effect in non-equilibrium flows
... the Knudsen number (Kn), defined as the ratio of the gas molecular mean free path λ to the device characteristic length ...The Knudsen layer is the local non-equilibrium region extending several mean ...
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Air entrainment in dynamic wetting : Knudsen effects and the influence of ambient air pressure
... Recent experiments on coating flows and liquid drop impact both demonstrate that wetting failures caused by air entrainment can be suppressed by reducing the ambient gas pressure. Here, it is shown that non-equilibrium ...
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Detailed Investigation of Hydrodynamics and Thermal Behaviors of Rarefied Shear Driven Flow Using DSMC
... Kn number eects and compare the values sampled directly from ...as Knudsen number increases, however, the rate of this increase slows down as the ow approaches the free molecular ...
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Non-equilibrium dynamics of dense gas under tight confinement
... (the Knudsen number, Kn) becomes appreciable in narrow channels, the Boltzmann equation is commonly used to describe the collective motion of a dilute gas from the hydrodynamic to the free-molecular flow ...
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Computing the near-wall region in gas micro- and nanofluidics : critical Knudsen layer phenomena
... Abstract. In order to capture critical near-wall phenomena in gas micro- and nanoflows within conventional CFD codes, we present scaled Navier-Stokes-Fourier (NSF) constitu- tive relations. Our scaling is mathematically ...
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Size-dependent Vibration and Instability of Magneto-electro-elastic Nano-scale Pipes Containing an Internal Flow with Slip Boundary Condition
... Assuming nonzero value for Kn (known as Knudsen number), one can model the interacting fluid flow as slip flow. The effect of Kn on eigenvalue diagram in this system is shown in Figure 4, for doubly-clamped ...
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Nonequilibrium dynamics of dense gas under tight confinement
... fixed Knudsen number (defined as Kn = λ/L), but is always smaller than that predicted by the Boltzmann ...famous Knudsen minimum disappears, and the mass flow rate increases with Kn, and is larger ...
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A kinetic theory description for external spherical flows with arbitrary Knudsen number by a moment method
... Lees suggested that the distribution function in the Maxwell integral equation of transfer b e represented by a weighting function expressed in terms of a number of parametric functions [r] ...
183
Lattice Boltzmann simulation of nonequilibrium effects in oscillatory gas flow
... the Knudsen number (Kn), defined as the ratio of the molecular mean free path λ to the characteristic length ...the Knudsen layer which extends a few molecular mean free paths away from the wall [8, ...
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A wall-function approach to incorporating Knudsen-layer effects in gas micro flow simulations
... A Knudsen layer (or kinetic boundary layer) always exists at the interface between a solid boundary and a moving ...the Knudsen layer within a shear flow bounded by a planar ...the Knudsen layer (at ...
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Computing the near-wall region in gas micro- and nanofluidics : critical Knudsen layer phenomena
... In the region close to a surface (within a few λ) the flow is highly non-equilibrial and the relationship between stress and strain is non-linear. This region is known as the Knudsen layer. Evidently, the linear ...
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Lattice Boltzmann simulation of rarefied gas flows in microchannels
... By applying the present boundary condition, we can capture the famous Knudsen paradox (Knudsen mini- mum) phenomenon. Toschi and Succi [25] have recently independently reproduced the Knudsen paradox. ...
5
Numerical investigating the gas slip flow in the microchannel heat sink using different materials
... Nusselt number in the slip flow regime is smaller than no slip flow ...Nusselt number, while the temperature-jump tends to decrease it, and the combined effect could result in an increase or a decrease in ...
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A Review On Enhancement Of Heat Transfer In Microchannel Heat Exchanger
... This review paper is comprehensive study of heat transfer in micro-channel heat exchanger. In this study we have demonstrated research based result and outcomes without any assumptions. In this paper we have discussed ...
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