Abstract
The phenomenon that flow resistances are higher in micro scale flow than in normal flow is clarified through the liquid viscosity. Based on the experimental results of deionized water flow in fused silica microtubes with the inner radii of 2.5 μm, 5 μm, 7.5 μm, and 10 μm, respectively, the relationship between water flow velocity and pressure gradient along the axis of tube is analyzed, which gradually becomes nonlinear as the radius of the microtube decreases. From the correlation, a viscosity model of water flow derived from the radius of microtube and the pressure gradient is proposed. The flow results modified by the viscosity model are in accordance with those of experiments, which are verified by numerical simulation software and the Hagen-Poiseuille equation. The experimental water flow velocity in a fused silica microtube with diameter of 5.03 μm, which has not been used in the fitting and derivation of the viscosity model, is proved to be comsistent with the viscosity model, showing a rather good match with a relative difference of 5.56%.
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References
Celata, G.P., Cumo, M., McPhail, S., et al.: Characterization of fluid dynamic behavior and channel wall effects in microtubes. Int. J. Heat Fluid Flow 27, 135–143 (2006)
Xu, B., Ooti, K.T., Wong. N.T.: Experimental investigation of flow friction for liquid flow in microchannels. Int. Commun. Heat Mass Transfer 27, 1165–1176 (2000)
Lelea, D., Nishio, S., Takano, K.: The experimental research on microtube heat transfer and fluid flow of distilled water. Int. J. Heat Mass Transfer 47, 2817–2830 (2004)
Judy, J., Maynes, D., Webb, B.W.: Characterization of frictional pressure drop for liquid flows through microchannels. Int. J. Heat Mass Transfer 45, 3477–3489 (2002)
Nagayama, G., Cheng, P.: Effects of interface wettability on microscale flow by molecular dynamics simulation. Int. J. Heat Mass Transfer 47, 501–513 (2004)
Parlak, N., Gur, M., Ari, V., et al.: Second law analysis of water flow through smooth microtubes under adiabatic conditions. Exp. Therm. Fluid Sci. 35, 40–47 (2011)
Qu, W.L., Mala, G.M., Li, D.Q.: Pressure-driven water flows in trapezoidal silicon microchannels. Int. J. Heat Mass Transfer 43, 353–364 (2000)
Li, Z.X., Du, D.X., Guo, Z.Y.: Experimental study on flow characteristics of liquid in circular microtubes. Microscale Therm. Eng. 7, 253–265 (2003)
Cui, H., Silber-Li, Z.: Flow characteristics of liquids in microtubes driven by a high pressure. Phys. Fluids 16, 1803–1810 (2004)
El-Genk, M., Yang, I.: Friction numbers and viscous dissipation heating for laminar flows of water in microtubes. J. Heat Trans. 130, 082405-1–13 (2008)
Qu, W., Mala, G., Li, D.: Heat transfer for water flow in trapezoidal silicon microchannels. Int. J. Heat Mass Transfer 43, 3925–3936 (2000)
Wang, F., Yue, X.A., Xu, S.L., et al.: Influence of wettability on flow characteristics of water through microtubes and cores. Chinese Sci. Bull. 54, 2256–2262 (2009)
Wen, S., Theory and Application of Microscale Flow Boundary. Metallurgical Industry Press, Beijing (2002) (in Chinese)
Nonino, C., Del, G., Savino, S.: Temperature dependent viscosity effects on laminar forced convection in the entrance region of straight ducts. Int. J. Heat Mass Transfer 49, 4469–4481 (2006)
Nonino, C., Del, G., Savino, S.: Temperature-dependent viscosity and viscous dissipation effects in microchannel flows with uniform wall heat flux. Heat Transfer Eng. 31, 682–691 (2010)
Xu, B., Ooi, K.T., Wong, T.N., et al.: Study on the viscosity of the liquid flowing in microgeometry. J. of Micromech. Microeng. 9, 377–384 (1999)
Li, Y.: Study of microscale nonlinear flow characteristics and flow resistance reducing methods, [Ph.D. Thesis]. Chinese Academy of Science, Beijing (2010) (in Chinese)
Park, H., Park, J.J., Son, S.Y., et al.: Fabrication of a microchannel integrated with inner sensors and the analysis of its laminar flow characteristics. Sensor Actuat. A 103, 317–329 (2003)
Mala, G., Li, D.: Flow characteristics of water in microtubes. Int. J. Heat Fluid Fl. 20, 142–148 (1999)
Yuan, Q., Zhao, Y.: Precursor film in dynamic wetting, electrowetting, and electro-elasto-capillarity. Physical Review Letters 104, 246101 (2010)
Liu, Z., Pang, Y., Shen, F.: Effects od geometry on the liquid flow and heat transfer in microchannels. Journal of Mechanical Engineering 48, 139–145 (2012)
Liu, Z., Pang, Y.: Influences of size and roughness of microchannel on friction factors under different pressures. Engineering Mechanics 29, 200–205 (2012)
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The project was supported by the National Natural Science Foundation of China (11072011 and 11002011) and the Doctoral Fund of Innovation of BJUT.
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Liu, ZM., Pang, Y. Effect of the size and pressure on the modified viscosity of water in microchannels. Acta Mech Sin 31, 45–52 (2015). https://doi.org/10.1007/s10409-015-0015-7
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DOI: https://doi.org/10.1007/s10409-015-0015-7