Investigation of Liquid Flow in Microchannels

Abstract

Liquid flow in microchannels is investigated both experimentally and numerically in this work. The experiments are carried out in microchannels with hydraulic diameters from 244 to 974 m at Reynolds numbers ranging from 230 to 6500. The pressure drop in these microchannels is measured in situ, and is also determined by correcting global measurements for

Investigation of heat transfer in rectangular microchannels

“…The disparity in conclusions regarding the applicability of conventional correlations to the prediction of single-phase microchannel heat transfer is evident from this table. This is in contrast to the success of conventional correlations in predicting pressure drop in microchannels as demonstrated in [10,11]. Most of the studies summarized in Table 4 indicate an under-prediction of the measured Nusselt numbers by conventional laminar correlations, while no consistent trend is observed for comparisons with correlations in the turbulent range.…”

“…The present work complements the detailed flow field and pressure drop measurements of Liu and Garimella [10]. A systematic investigation is conducted of single-phase heat transfer in microchannels of hydraulic diameters ranging from 318 to 903 m, at flow Reynolds numbers of 300 to…”

“…A schematic of the experimental facility used in this investigation, which was modified from that used for pressure drop measurements in [10], is shown in Fig. 1.…”

“…Liu and Garimella [10] showed that conventional correlations offer reliable predictions for the laminar flow characteristics in rectangular microchannels over a hydraulic diameter range of 244 to 974 m. Judy et al [11] made extensive frictional pressure drop measurements for…”

Boiling and Evaporation in Small Diameter Channels

“…Sobhan and Garimella [28] found existing "microchannel" friction and heat transfer predictions to produce mutually contradictory results in both regimes, which, in effect, confirms Obot's conclusion about conventional correlations being acceptable on the average. Several recent studies have compared careful measurements of pressure loss or velocity profiles for liquids flowing in microchannels to standard results [29][30][31]; agreement is excellent down to hydraulic diameters of 75 µm or so. While some deviations have been reported in smaller channels, no new physical phenomena have been identified.…”