Simulation of nanofluid flow at low Reynolds number in a microchannel with one-sided sudden expansion under the effect of a magnetic field

Document Type : Original Article

Authors

• Foroozan Moradi
• Pedram Pournaderi

Department of Mechanical Engineering, Faculty of Engineering, Yasouj University, Yasouj, Iran.

10.22067/jacsm.2023.79298.1143

Abstract

In this study, the magnetic field effect on the hydrodynamics and heat transfer of the laminar flow of a nanofluid in a microchannel with one-sided sudden expansion at a low Reynolds number is investigated. The governing equations including mass, momentum, and energy conservation equations are discretized and solved on a staggered grid using the finite difference method by developing a Fortran code. The simulation results show that at a low Reynolds number, no vortex is formed after the step. In the presence of a magnetic field, the friction coefficient decreases with volume fraction. At a volume fraction of 0.04, this reduction in comparison with water at Hartmann numbers of 20 and 40 is 25 and 18 percent, respectively. By applying the magnetic field, the friction factor increases. For nanofluid with a volume fraction of 0.04, the enhancement of average friction factor in comparison with water at Hartmann numbers of 20 and 40 is 176 and 337 percent, respectively. At a low Reynolds number, the magnetic field effect on the Nusselt number is negligible. The Nusselt number decreases with volume fraction. At a volume fraction of 0.04, a reduction of about 12 percent is observed in the Nusselt number in comparison with water. Examining the performance evaluation criteria shows that applying a magnetic field improves the system's performance. At a Hartmann number of 20 and volume fraction of 0.04, an enhancement of about 11 percent in performance coefficient is observed in comparison with the case that the magnetic field is absent.

Keywords

• Nanofluid
• Microchannel
• Sudden expansion
• Magnetic field
• Low Reynolds number

Main Subjects

• Fluid mechanics

---

References

[1] S.  K. Bala, L.  K. Saha, M. A. Hossain, “Simulation of forced convection in a channel containing three obstacles over backward and forward facing  steps by LBM,” International Journal of Applied and Computational Mathematics, vol. 5, pp. 1-19, 2019.

[2] J. C. Maxwell, Eds, “A Treatise on Electricity and Magnetism,” Oxford: Clarendon press, 1873.

[3] S. U. Choi, J. A.  Eastman, Enhancing thermal conductivity of fluids with nanoparticles, ASME Conference, USA, pp. 99–105, (1995).

[4] O. Mahian, L. Kolsi, M. Amani, P. Estellé, G. Ahmadi, C. Kleinstreuer, J. S. Marshall, M. Siavashi, R.A. Taylor, H. Niazmand, S. Wongwises, “Recent advances in modeling and simulation of nanofluid flows-Part I: Fundamentals and theory,” Physics Reports, vol. 790, pp.1-48, 2019.

[5]A. Sh. Kherbeet, H. A. Mohammed, B. H. Salman, H. E. Ahmed, O. A. Alawi, “Experimental and numerical study of nanofluid flow and heat transfer over microscale backward-facing step,” International Journal of Heat and Mass Transfer, vol. 79, pp. 858–867, 2014.

[6] F. Selimefendigil, H. F. Öztop, “Forced convection and thermal predictions of pulsating nanofluid flow over a backward facing step with a corrugated bottom wall,” International Journal of Heat and Mass Transfer, vol. 110, pp. 231-247, 2017.

[7] H. A. Mohammed, F. Fathinia, H. B. Vuthaluru, S. Liu, “CFD based investigations on the effects of blockage shapes on transient mixed convective nanofluid flow over a backward facing step,” Powder Technology, vol, 346, pp. 441-451, 2019.

[8] H. Moayedi, “Numerical investigation of the effect of oscillating injection nanofluid flow on forced convection heat transfer enhancement over a backward-facing step,” The European Physical Journal Plus, vol. 135, pp. 924, 2020.

[9] P. Pournaderi, M. Aram, “Numerical investigation of nanofluid flow and heat transfer over a backward-facing step,” Engineering and Applied Science Research, vol. 47, pp. 401-413, 2020.

[10] D. Yang, B. Sun, T. Xu, B. Liu, H. Li, “Experimental and numerical study on the flow and heat transfer characteristic of nanofluid in the recirculation zone of backward-facing step microchannels,” Applied Thermal Engineering, vol. 199, pp.117527, 2021.

[11] T. Onishi, T. Yamamoto, “Numerical Analysis of Effects of Aspect Ratio of Rod-like Nanoparticles on Thermal and Flow Behavior of Nanofluids in Backward-facing Step Flows,” Nihon Reoroji Gakkaishi, vol. 50, pp.323-332, 2022.

[12] J. Hartmann, F. Lazarus., “Experimental investigations on the flow of mercury in a homogeneous magnetic field,” Munksgaard, 1937.‏

[13] F. Selimefendigil, H. Oztop, “Influence of inclination angle of magnetic field on mixed convection of nanofluid flow over a backward facing step and entropy generation,” Advanced Powder Technology, vol. 26, pp. 1663–1675, 2015.

[14] Z. Mehrez, A. E. Casfi, “Forced convection magnetohydrodynamic Al2O3–Cu/water hybrid nanofluid flow over a backward-facing step,” Journal of Thermal Analysis and Calorimetry, vol. 135, pp.1417–1427, 2018.

[15] F. Selimefendigil, C. S. Ozkan, H. Oztop, “Electrical conductivity effect on MHD mixed convection of nanofluid flow over a backward-facing step,” Journal of Central South University, vol. 26, pp. 1133–1145, 2019.

[16] S. Hussain, S. E. Ahmed, “Unsteady MHD forced convection over a backward facing step including a rotating cylinder utilizing Fe3O4-water ferrofluid,” Journal of Magnetism and Magnetic Materials, vol. 484, pp. 356-366, 2019.

[17] B. P. Geridönmez, H. F. Öztop, “Effects of inlet velocity profiles of hybrid nanofluid flow on mixed convection through a backward facing step channel under partial magnetic field,” Chemical Physics, vol. 540, pp. 111010, 2020.

[18] T. D. Manh, A. M. Abazari, M. Barzegar Gerdroodbary, N. D. Nam, R. Moradi, H. Babazadeh, “Computational simulation of variable magnetic force on heat characteristics of backward-facing step flow,” Journal of Thermal Analysis and Calorimetry, vol. 144, pp.1585-1596, 2021.

[19] K. Ghachem, F. Selimefendigil, B. M. Alshammari, C. Maatki, L. Kolsi, “Coupled Effects of Using Magnetic Field, Rotation and Wavy Porous Layer on the Forced Convection of Hybrid Nanoliquid Flow over 3D-Backward Facing Step,” Nanomaterials, vol. 12, p.2466, 2022.

[20] P. Pournaderi, M. Deilami, “Modeling nanofluid droplet impingement on a superheated surface,” Powder Technology, vol. 381, pp. 68-81, 2021.

[21] P. Pournaderi, A. R. Pishevar, “A numerical investigation of droplet impact on a heated wall in the film boiling regime,” Heat and Mass Transfer, vol. 48, pp. 1525-1538, 2012.

[22] M. Corcione, “Heat transfer features of buoyancy-driven nanofluids inside rectangular enclosures differentially heated at the sidewalls,” International Journal of Thermal Sciences, vol. 49, pp.1536-1546, 2010.

[23] R. S. Vajjha, D. K. Das, “Experimental determination of thermal conductivity of three nanofluids and development of new correlations,” International Journal of Heat and Mass Transfer, vol. 52, pp.4675-4682, 2009.

[24] T. L. Bergman, A. S. Lavine, F. P. Incropera, and D.P. DeWitt, Introduction to heat transfer, John Wiley & Sons, 2011. [E-book] Available: books.google.com.

[25] A. K. Hilo, A. A. Iborra, M. T. H. Sultan, M. F. A. Hamid, “Experimental study of nanofluids flow and heat transfer over a backward-facing step channel,” Powder Technology, vol. 372, pp. 497-505, 2020.