Pressure drop measurements in a microchannel

Abstract

Recent de®elopments in micro-

Pressure drops of single and two-phase flows through T-type microchannel mixers

“…5 and 6, in microchannels of the two micromixers, the experimentally derived friction factor is a function of Reynolds number for N 2 Consequently, we can conclude that in fully developed, incompressible and isothermal laminar flow region, fluid behavior in microchannels with diameters of several hundred micrometers still obeys classic theory, which is also proved by many other authors [19][20][21][22][23][24][25]. Even if such micro effects as electro-viscous effects for liquid flow and roughness effects exist [8][9][10][11][12][13][14][15][16], they only play minor roles in determining the friction factor of fluid flow in the smooth or near smooth microchannels used in this work. In other words, without excluding the experiment uncertainties, the influences of these effects are hard to recognize.…”

“…For gas and liquid single-phase flows in microchannels, contradictory experimental and simulation results exist [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. From the viewpoints of actual applications of microchannel reactors, we are mainly interested in fluid laminar flow behavior in microchannels with diameters of several hundred micrometers (termed "large microchannels" in the following paragraphs), where compressible effects and rarefaction effects are thought to be negligible.…”

“…Currently available research papers on fluid laminar flow in large microchannels reveal that the conclusions can be mainly classified into three categories (divided by the relationship between fRe and C): (1) fRe > C, i.e., fluid laminar flow in microchannels exhibits a higher pressure drop [8][9][10][11][12][13][14][15][16]; (2) fRe < C, i.e., the pressure drop of fluid laminar flow in microchannels is less than that predicted by classic theory [17,18]; and (3) fRe = C, i.e., fluid laminar flow in microchannels is still consistent with classic theory [19][20][21][22][23][24][25]. More details are tabulated in Table 1.…”

Numerical Analysis About the Influence of Inappropriate Shape of the Cross-Section of Microchannels in Laminar Flow

“…A lot of experimental studies [1,2,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], besides theoretical [22][23][24] and numerical studies [5,[25][26][27][28], have been carried out, in the past decades, seeking to investigate the hydrodynamics and heat transfer characteristics in microscale. The results obtained in several of these studies show diversions among themselves and, also, with the conventional theory.…”

Effect of Surface Roughness on Micro-channel Flow of Dilute Polymer Solutions

“…Pfund 1) 128 mm 521 mm Celata 2) 70 mm 326 mm 126 mm In this study, we investigated the influence of wall surface roughness on the pressure drop in micro-channel flow of dilute polymer solutions with two different channel heights, 100 and 50 mm. Tested channel surface roughness are Ra = 0.2, 1.0, 1.6, 2.5, 4.7, and 10.0 mm.…”