Document Type : Original Article


Department of Mechanical Engineering, Shahrekord University, Shahrekord, Iran


In this study, forced convection heat transfer of water/alumina Nano fluid in a rectangular microchannel with cross-flow injection is studied. The Nano fluid enters the microchannel with a temperature of 293 K and cools its walls. The upper wall of the microchannel is at constant temperature of 303 K. On the lower wall, there are two holes for injection of Nano fluid flow. Other parts of the microchannel wall are insulated. Slip velocity boundary condition is used for the walls of the microchannel. Simulations are performed for different injection velocities and the results are presented as velocity and temperature fields, and variation of the Nusselt number. The results show that the slip velocity on the channel wall and the Nusselt number increase by increasing the injection velocity. It is revealed that the Nusselt number is maximum at the channel entrance and decreases along the channel. After each injection, local Nusselt number increases due to the increase of the temperature gradient in the microchannel. Moreover, an optimal value for the ratio of the injection velocity to the inlet velocity is achieved using performance evaluation criteria (PEC). It is concluded that  is an optimal value of the injection velocity, leading to maximum PEC.


[1]     Malvandi, A., Ganji, D. D., Effects of Nanoparticle Migration and Asymmetric Heating On Magnetohydrodynamic Forced Convection of Alumina/Water Nanofluid in Microchannels, European Journal of Mechanics-B/Fluids, Vol. 52, 2015, pp. 169-184.
[2]     Mokrani, O., Bourouga, B., Castelain, C., and Peerhossaini, H., Fluid Flow and Convective Heat Transfer in Flat Microchannels, International Journal of Heat and Mass Transfer, Vol. 52, No. 5-6, 2009, pp. 1337-1352.
[3]     Choi, S. U. S., Singer, D. A., and Wang, H. P., Developments and Applications of Non-Newtonian Flows, Asme Fed, Vol. 66, 1995, pp. 99-105.
[4]     Akbarinia, A., Abdolzadeh, M., and Laur, R., Critical Investigation of Heat Transfer Enhancement Using Nanofluids in Microchannels with Slip and Non-Slip Flow Regimes, Applied Thermal Engineering, Vol. 31, No. 4, 2011, pp. 556-565.
[5]     Bhattacharya, P., Samanta, A. N., and Chakraborty, S., Numerical study of Conjugate Heat Transfer in Rectangular Microchannel Heat Sink with Al2O3/H2O Nano Fluid, Heat and Mass Transfer, Vol. 45, No. 10, 2009, pp. 1323-1333.
[6]     Devendiran, D. K., Amirtham, V. A., A Review On Preparation, Characterization, Properties and Applications of Nano Fluids, Renewable and Sustainable Energy Reviews, Vol. 60, 2016, pp. 21-40.
[7]     Duangthongsuk, W., Wongwises, S., Measurement of Temperature-Dependent Thermal Conductivity and Viscosity of TiO2-Water Nano Fluids, Experimental Thermal and Fluid Science, Vol. 33, No. 4, 2009, pp. 706-714.
[8]     Ho, C. J., Wei, L. C., and Li, Z. W., An Experimental Investigation of Forced Convective Cooling Performance of a Microchannel Heat Sink with Al2O3/Water Nano Fluid. Applied Thermal Engineering, Vol. 30, No. 2-3, 2010, pp. 96-103.
[9]     Lee, J., Mudawar, I., Assessment of the Effectiveness of Nano Fluids for Single-Phase and Two-Phase Heat Transfer in Micro-Channels, International Journal of Heat and Mass Transfer, Vol. 50, No. 3-4, 2007, pp. 452-463.
[10]  Masuda, H., Ebata, A., and Teramae, K., Alteration of Thermal Conductivity and Viscosity of Liquid by Dispersing Ultra-Fine Particles, Dispersion of Al2O3, SiO2 and TiO2 Ultra-Fine Particles, 1993.  
[11]  Mintsa, H. A., Roy, G., Nguyen, C. T., and Doucet, D., New Temperature Dependent Thermal Conductivity Data for Water-Based Nano Fluids, International Journal of Thermal sciences, Vol. 48, No. 2, 2009, pp. 363-371.
[12]  Reddy, M. C. S., Rao, V. V., Experimental Studies On Thermal Conductivity of Blends of Ethylene Glycol-Water-Based TiO2 Nano Fluids, International Communications in Heat and Mass Transfer, Vol. 46, 2013, pp. 31-36.
[13]  Santra, A. K., Sen, S., and Chakraborty, N., Study of Heat Transfer Due to Laminar Flow of Copper–Water Nano Fluid Through Two Isothermally Heated Parallel Plates, International Journal of Thermal Sciences, Vol. 48, No. 2, 2009, pp. 391-400.
[14]  Xuan, Y., Li, Q. Heat Transfer Enhancement of Nano Fluids, International Journal of Heat and Fluid Flow, Vol. 21, No. 1, 2000, pp. 58-64.
[15]  Kamali, R., Binesh, A. R., Numerical Investigation of Heat Transfer Enhancement Using Carbon Nanotube-Based Non-Newtonian Nano Fluids, International Communications in Heat and Mass Transfer, Vol. 37, No. 8, 2010, pp. 1153-1157.
[16]  Jang, S. P., Choi, S. U., Cooling Performance of a Microchannel Heat Sink with Nano Fluids, Applied Thermal Engineering, Vol. 26, No. 17-18, 2006, pp. 2457-2463.
[17]  Jung, J. Y., Oh, H. S., and Kwak, H. Y., Forced Convective Heat Transfer of Nanofluids in Microchannels, In Asme 2006 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2006, pp. 327-332,
[18]  Koo, J., Kleinstreuer, C., Laminar nanofluid flow in microheat-sinks, International Journal of Heat and Mass Transfer, Vol. 48, No. 13, 2005, pp. 2652-2661.
[19]  Madani, K., Numerical Investigation of Cooling a Ribbed Microchannel Using Nanofluid, Journal of Thermal Engineering, Vol. 4, No, 6, 2018, pp. 2408-2422.
[20]  Moghari, R. M., Akbarinia, A., Shariat, M., Talebi, F., and Laur, R., Two Phase Mixed Convection Al2O3–Water Nanofluid Flow in an Annulus, International Journal of Multiphase Flow, Vol. 37, No. 6, 2011, pp. 585-595.
[21]  Shiriny, A., Bayareh, M., and Nadooshan, A. A., Nanofluid flow in a microchannel with inclined cross-flow injection. SN Applied Sciences, Vol. 1, No. 9, 2019, pp. 1015.
[22]  Tsai, T. H., Chein, R., Performance Analysis of Nanofluid-Cooled Microchannel Heat Sinks, International Journal of Heat and Fluid Flow, Vol. 28, No. 5, 2007, pp. 1013-1026.
[23]  Bagheri, H., Nadooshan, A. A., The Effects of Hybrid Nano-Powder of Zinc Oxide and Multi Walled Carbon Nanotubes On the Thermal Conductivity of an Antifreeze, Physica E: Low-Dimensional Systems and Nanostructures, Vol. 103, 2018, pp. 361-366.
[24]  Abdollahi, A., Mohammed, H. A., Vanaki, S. M., and, Sharma, R. N., Numerical investigation of fluid flow and heat transfer of nanofluids in microchannel with longitudinal fins. Ain Shams Engineering Journal, Vol. 9, No, 4, 2018, pp. 3411-3418.
[25]  Ambreen, T., Kim, M. H., Effects of Variable Particle Sizes On Hydrothermal Characteristics of Nanofluids in a Microchannel, International Journal of Heat and Mass Transfer, Vol. 120, 2018, pp. 490-498.
[26]  Kahani, M., Simulation of Nano Fluid Flow Through Rectangular Microchannel by Modified Thermal Dispersion Model, Heat Transfer Engineering, 2019, pp. 1-16.
[27]  Afrand, M., Karimipour, A., Nadooshan, A. A., and Akbari, M., The Variations of Heat Transfer and Slip Velocity of Fmwnt-Water Nano-Fluid Along the Micro-Channel in The Lack and Presence of a Magnetic Field, Physica E: Low-Dimensional Systems and Nanostructures, Vol. 84, 2016, pp. 474-481.
[28]  Nemati, H., Farhadi, M., Sedighi, K., Ashorynejad, H. R., and Fattahi, E. J. S. I., Magnetic Field Effects On Natural Convection Flow of Nano Fluid in A Rectangular Cavity Using the Lattice Boltzmann Model, Scientia Iranica, Vol. 19, No. 2, 2012, pp. 303-310.
[29]  Zhao, G., Wang, Z., and Jian, Y., Heat Transfer of the Mhd Nanofluid in Porous Microtubes Under the Electrokinetic Effects, International Journal of Heat and Mass Transfer, Vol. 130, 2019, pp. 821-830.
[30]  Jha, B. K., Aina, B., Role of Suction/Injection On Steady Fully Developed Mixed Convection Flow in a Vertical Parallel Plate Microchannel, Ain Shams Engineering Journal, 2016.
[31]  Lopez, A., Ibanez, G., Pantoja, J., Moreira, J., and Lastres, O., Entropy Generation Analysis of MHD Nano Fluid Flow in A Porous Vertical Microchannel with Nonlinear Thermal Radiation, Slip Flow and Convective-Radiative Boundary Conditions, International Journal of Heat and Mass Transfer, Vol. 107, 2017, pp. 982-994.
[32]  Jalali, E., Karimipour, A., Simulation the Effects of Cross-Flow Injection On the Slip Velocity and Temperature Domain of a Nano Fluid Flow Inside a Microchannel, International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 29, No. 5, 2019, pp. 1546-1562.
[33]  Pak, B. C., Cho, Y. I., Hydrodynamic and Heat Transfer Study of Dispersed Fluids with Submicron Metallic Oxide Particles, Experimental Heat Transfer an International Journal, Vol. 11, No. 2, 1998, pp. 151-170.
[34]  Buongiorno, J., Convective Transport in Nano Fluids, Journal of Heat Transfer, Vol. 128, No. 3, 2006, pp. 240-250.
[35]  Brinkman, H. C., The Viscosity of Concentrated Suspensions and Solutions, The Journal of Chemical Physics, Vol. 20, No. 4, 1952, pp. 571-571.
[36]  Patel, H. E., Anoop, K. B., Sundararajan, T., and Das, S. K., A Micro-Convection Model for Thermal Conductivity of Nano Fluids, In International Heat Transfer Conference 13. Begel House Inc., 2006.