Analysis of single phase convective heat transfer in microtubes and microchannels

Çetin, Barbaros
Heat transfer analysis of two-dimensional, incompressible, constant property, hydrodynamically developed, thermally developing, single phase laminar flow in microtubes and microchannels between parallel plates with negligible axial conduction is performed for constant wall temperature and constant wall heat flux thermal boundary conditions for slip flow regime. Fully developed velocity profile is determined analytically, and energy equation is solved by using finite difference method for both of the geometries. The rarefaction effect which is important for flow in low pressures or flow in microchannels is imposed to the boundary conditions of the momentum and energy equations. The viscous dissipation term which is important for high speed flows or flows in long pipelines is included in the energy equation. The effects of rarefaction and viscous heating on temperature profile and local Nusselt number are discussed. The results of the numerical method are verified with the well-known analytical results of the flow in macrochannels (i.e. Kn =0, Br =0) and with the available analytical results of flow in microchannels for simplified cases. The results show significant deviations from the flow in macrochannels.


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In this study, effect of surface roughness on convective heat transfer and fluid flow in two dimensional parallel plate microchannels is analyzed by numerically. For this purpose, single-phase, developing, laminar fluid flow at steady state and in the slip flow regime is considered. The continuity, momentum, and energy equations for Newtonian fluids are solved numerically for constant wall temperature boundary condition. Slip velocity and temperature jump at wall boundaries are imposed to observe the rarefa...
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Akman, Mehmet Nazım; Oral, Süha; Department of Mechanical Engineering (2008)
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Citation Formats
B. Çetin, “Analysis of single phase convective heat transfer in microtubes and microchannels,” M.S. - Master of Science, Middle East Technical University, 2005.