Gaseous slip flow affected by inclined low magnetic field using second‐order boundary conditions

The constant growth of the studies on microchannel flows has brought under question the validity of the relations for heat transfer and fluid flow, which are usually employed at the macroscales. Rarefied flows in the slip-flow region have attracted much attention and solutions have been developed using first- and second-order boundary conditions. These models need to be experimentally validated through careful test in order to be able to use them for more complex problems and engineering applications. In the current work the error propagation analysis is applied to a set of error-free measurements artificially generated in order to assess the influence of the uncertainty on each of the measured quantities on the determination of the Poiseuille number for rarefied flows: it is shown that the most limiting factor is the accuracy on the tube diameter, while flowrate and pressure drop errors can be kept contained provided the measurement ranges for the transducers are suitably chosen. The total uncertainty is also calculated and the limit of the investigable Reynolds numbers defined. The possibility of experimentally evidencing the differences between first- and second-order boundary conditions is investigated and it is concluded that this is the case only for highly rarefied flows ( Kn > 0.5).

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Magnetic field effect on second order slip flow of nanofluid over a stretching/shrinking sheet with thermal radiation effect

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2014.12.010 ◽

2015 ◽

Vol 381 ◽

pp. 243-257 ◽

Cited By ~ 74

Author(s):

A.K. Abdul Hakeem ◽

N. Vishnu Ganesh ◽

B. Ganga

Keyword(s):

Magnetic Field ◽

Thermal Radiation ◽

Field Effect ◽

Radiation Effect ◽

Slip Flow ◽

Magnetic Field Effect ◽

Second Order ◽

Shrinking Sheet ◽

Thermal Radiation Effect

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Constant Wall Temperature Nusselt and Poiseuille Numbers in Rectangular Microchannels

ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference, Volume 1 ◽

10.1115/ht2007-32465 ◽

2007 ◽

Cited By ~ 2

Author(s):

Jennifer van Rij ◽

Tim Ameel ◽

Todd Harman

Keyword(s):

Aspect Ratio ◽

Boundary Conditions ◽

Viscous Dissipation ◽

Wall Temperature ◽

Rectangular Channel ◽

Slip Flow ◽

Second Order ◽

Constant Wall Temperature ◽

Axial Conduction ◽

Accommodation Coefficients

Slip flow convective heat transfer and friction loss characteristics are numerically evaluated for constant wall temperature rectangular microchannels. The effects of rarefaction, accommodation coefficients, aspect ratio, second-order slip boundary conditions, axial conduction, and viscous dissipation with flow work are each considered. Second-order slip boundary conditions, axial conduction, and viscous dissipation with flow work effects have not been studied previously for rectangular channel slip flows. The effects of each of these parameters on the numerically computed convective heat transfer rate and friction loss are evaluated through the Nusselt number and Poiseuille number respectively. The numerical results are obtained using a continuum-based computational fluid dynamics algorithm that includes second-order slip flow and temperature jump boundary conditions. Numerical results for the three-dimensional, fully developed Nusselt and Poiseuille numbers are presented as functions of Knudsen number, first- and second-order velocity slip and temperature jump coefficients, aspect ratio, Brinkman number, and Peclet number. Effects of rarefaction, accommodation coefficients, and aspect ratio are consistent with previously reported analytical results for rectangular channel constant wall temperature flows. The effects of second-order slip terms, axial conduction and viscous dissipation are also shown to significantly affect the Nusselt and Poiseuille numbers.

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