Slip flow through a converging microchannel: experiments and 3D simulations
DSpace at IIT Bombay
View Archive InfoField | Value | |
Title |
Slip flow through a converging microchannel: experiments and 3D simulations
|
|
Creator |
VARADE, V
AGRAWAL, A PRADEEP, AM |
|
Subject |
RAREFIED-GAS FLOW
SUDDEN CONTRACTION PRESSURE-DROP MICROPUMP APPLICATIONS HEAT-TRANSFER MICROTUBES DIFFUSER/NOZZLE EXPANSION VALVES MICRONOZZLE/DIFFUSER converging microchannel slip flow Knudsen number Mach number |
|
Description |
An experimental and 3D numerical study of gaseous slip flow through a converging microchannel is presented in this paper. The measurements reported are with nitrogen gas flowing through the microchannel with convergence angles (4 degrees, 8 degrees and 12 degrees), hydraulic diameters (118, 147 and 177 mu m) and lengths (10, 20 and 30 mm). The measurements cover the entire slip flow regime and a part of the continuum and transition regimes (the Knudsen number is between 0.0004 and 0.14); the flow is laminar (the Reynolds number is between 0.5 and 1015). The static pressure drop is measured for various mass flow rates. The overall pressure drop increases with a decrease in the convergence angle and has a relatively large contribution of the viscous component. The numerical solutions of the Navier-Stokes equations with Maxwell's slip boundary condition explore two different flow behaviors: uniform centerline velocity with linear pressure variation in the initial and the middle part of the microchannel and flow acceleration with nonlinear pressure variation in the last part of the microchannel. The centerline velocity and the wall shear stress increase with a decrease in the convergence angle. The concept of a characteristic length scale for a converging microchannel is also explored. The location of the characteristic length is a function of the Knudsen number and approaches the microchannel outlet with rarefaction. These results on gaseous slip flow through converging microchannels are observed to be considerably different than continuum flow.
|
|
Publisher |
IOP PUBLISHING LTD
|
|
Date |
2016-01-15T08:19:35Z
2016-01-15T08:19:35Z 2015 |
|
Type |
Article
|
|
Identifier |
JOURNAL OF MICROMECHANICS AND MICROENGINEERING, 25(2)
0960-1317 1361-6439 http://dx.doi.org/10.1088/0960-1317/25/2/025015 http://dspace.library.iitb.ac.in/jspui/handle/100/18148 |
|
Language |
en
|
|