Effects of condensation in microchannels with a porous boundary: analytical investigation on heat transfer and meniscus shape
AUTOR(ES)
Riehl, R. R., Ochterbeck, J. M., Seleghim, Jr, P.
FONTE
Journal of the Brazilian Society of Mechanical Sciences
DATA DE PUBLICAÇÃO
2002-07
RESUMO
In two-phase miniature and microchannel flows, the meniscus shape must be considered due to effects that are affected by condensation and/or evaporation and coupled with the transport phenomena in the thin film on the microchannel wall, when capillary forces drive the working fluid. This investigation presents an analytical model for microchannel condensers with a porous boundary, where capillary forces pump the fluid. Methanol was selected as the working fluid. Very low liquid Reynolds numbers were obtained (Re~6), but very high Nusselt numbers (Nu~150) could be found due to the channel size (1.5 mm) and the presence of the porous boundary. The meniscus calculation provided consistent results for the vapor interface temperature and pressure, as well as the meniscus curvature. The obtained results show that microchannel condensers with a porous boundary can be used for heat dissipation with reduced heat transfer area and very high heat dissipation capabilities.
Documentos Relacionados
- Heat transfer in channels with solid and porous baffles.
- Heat transfer in porous media
- Effects of temperature-dependent viscosity on fluid flow and heat transfer in a helical rectangular duct with a finite pitch
- Experimental investigation of the liquid volumetric mass transfer coefficient for upward gas-liquid two-phase flow in rectangular microchannels
- Investigation of hydrodynamics and heat transfer in pseudo 2D spouted beds with and without draft plates