Main Article Content

Abstract

Numerical simulation is performed to explore the convective heat transfer characteristics of Fe3O4-H2O nanofluid contained in a right-angle triangular cavity considering three types of thermal boundary conditions at the bottom wall. No heat is allowed to escape through the insulated vertical wall, whereas the inclined wall is kept colder than the bottom one. A sloping magnetic field whose strength is unvarying acts upon the cavity. The physical model is converted to the mathematical form through coupled highly nonlinear partial differential equations. These equations are then transformed into the non-dimensional form with the help of a group of transformations of variables. A very robust pde solver COMSOL Multiphysics that uses the finite element method (FEM) of Galerkin type is applied to carry out the numerical calculation. Heat transfer escalation through middling Nusselt number at the lowermost cavity wall is explored for diverse model parameters and thermal circumstances. The outcomes lead us to conclude that a higher degree of heat transfer is accomplished by reducing the dimension of nanoparticles and aggregating the buoyancy force through the Rayleigh number. It is highest when there is a magnetic field leaning angle of 900 and the lowermost wall is heated homogenously.

 

Keywords

Nanofluid Free convection Triangular cavity Sloping magnetic field FEM

Article Details

References

  1. Kaushik, S.C., Kumar, R., Garg, H.P. and Prakash, J. Transient analysis of a triangular built-in-storage solar water-heater under winter conditions. Heat Recovery Systems and Combined Heat and Power, 1994, 14, 337–341.
  2. Asan, H. and Namli, L. Laminar natural convection in a pitched roof of triangular cross-section: summer day boundary conditions. Energy and Buildings, 2000, 33, 69–73.
  3. Omri, A., Orfi, J. and Nasrallah, J. B. Natural convection effects in solar stills. Desalination, 2005, 183, 173–178.
  4. Anandalakshmi, R. and Basak, T. Heat flow visualization in rhombic enclosures due to isothermal and non-isothermal heating at the bottom wall. International Journal of Heat and Mass Transfer, 2012, 55, 325–1342.
  5. Flack, R.D., Konopnicki, T. and Rooke, J.H. The measurement of natural convective heat transfer in triangular enclosures. Journal of Heat Transfer, 1979, 101, 770–772.
  6. Flack, R.D. The experimental measurement of natural convection heat transfer in triangular enclosures heated or cooled from below. Journal of Heat Transfer, 1980, 102, 770–772.
  7. Akinsete, V.A. and Coleman, T.A. Heat transfer by steady laminar free convection in triangular enclosures. International Journal of Heat and Mass Transfer, 1982, 25, 991–998.
  8. Ridouane, E.I., Campo, A. and Chang, J.Y. Natural convection patterns in right-angled triangular cavities with heated vertical sides and cooled hypotenuses. Journal of Heat Transfer, 2005,127, 1181–1186.
  9. Varol, Y., Oztop, H.F. and Varol, A. Effects of thin fin on natural convection in porous triangular enclosures. International Journal of Thermal Sciences, 2008, 46, 1033–1045.
  10. Basak, T., Aravind, G. and Roy, S. Visualization of heat flow due to natural convection within triangular cavities using Bejan’s heatline concept. International Journal of Heat and Mass Transfer, 2009, 52, 2824–2833.
  11. Yesiloz, G. and Aydin, O. Laminar natural convection in right-angled triangular enclosures heated and cooled on adjacent walls. International Journal of Heat and Mass Transfer, 2013, 60, 365–374.
  12. Ozoe, H. and Okada, K. The effect of the direction of the external magnetic field on the three-dimensional natural convection in a cubical enclosure. International Journal of Heat and Mass Transfer, 1989, 32, 1939-1954.
  13. Pirmohammadi, M. and Ghassemi, M. Effect of magnetic field on convection heat transfer inside a tilted square enclosure. Int. Commun. Heat Mass Transfer, 2009, 36, 776-780.
  14. Sathiyammmoorthy, M. and Chamkha, A.J. Effect of magnetic field on natural convection flow in a liquid gallium filled square cavity for linearly heated side walls. International Journal of Thermal Sciences, 2010, 49, 1856-1865.
  15. Grosan, T., Renvic, C., Pop, I. and Ingham, D.B. Magnetic field and internal heat generation effects on free convection in a rectangular cavity filled with a porous medium. International Journal of Heat and Mass Transfer, 2009, 52, 1525-1533.
  16. Choi, S.U.S. Enhancing thermal conductivity of fluids with nanoparticles. In: Signier DA, Wang HP (eds.) Development and applications of non-Newtonian flows. American Society of Mechanical Engineers Fluids Engineering Division, vol.231/MD 1995, 66, 99–105.
  17. Wong, K.V. and De Leon, O. Applications of nanofluids: current and future. Advances in Mechanical Engineering, 2010; Article ID 519659 (11 pages).
  18. Das, S.K., Choi, S.U.S., Yu, W. and Pradeep, T. Nanofluids: Science and Technology. Wiley, New Jersey, 2007.
  19. Mahian, O., Kianifar, A., Kalogirou, S.A., Pop, I. and Wongwises, S. A review of the applications of nanofluids in solar energy. International Journal of Heat and Mass Transfer, 2013, 57, 582–594.
  20. Kakac, S. and Pramuanjaroenkij, A. Review of convective heat transfer enhancement with nanofluids. International Journal of Heat and Mass Transfer, 2009, 52, 3187–3196.
  21. Uddin, M.J., Al Kalbani, K.S., Rahman, M.M., Alam, M.S., Al-Salti, N. and Eltayeb, I.A. Fundamentals of nanofluids: evolution, applications and new theory. International Journal of Biomathematics and Systems Biology, 2015, 2 (1), 1-32.
  22. Ghasemi, B. and Aminossadati, S.M. Mixed convection in a lid-driven triangular enclosure filled with nanofluids. International Communications in Heat and mass Transfer, 2010, 37, 1142–1148.
  23. Billah, M.M., Rahman, M.M., Razzak, M.A., Saidur, R. and Mekhilef, S. Unsteady buoyancy-driven heat transfer enhancement of nanofluids in an inclined triangular enclosure, International Communications in Heat and Mass Transfer, 2013, 49, 115–127.
  24. Al Kalbani, K.S., Rahman, M.M., Alam, M.S., Al-Salti, N. and Eltayeb, I.A. Buoyancy induced heat transfer flow inside a tilted square enclosure filled with nanofluids in the presence of oriented magnetic field. Heat Transfer Engineering, 2018, 39, 511-525.
  25. Buongiorno, J. Convective transport in nanofluids. Journal of Heat Transfer, 2006, 128, 240-250.
  26. Sheremet, M.A. and Pop, I. Free convection in a triangular cavity filled with a porous medium saturated by a nanofluid; Buongiorno's mathematical model. International Journal of Numerical Methods for Heat and Fluid Flow, 2015, 25, 1138-1161.
  27. Rahman, M.M., Alam, M.S., Al-Salti, N. and Eltayeb, I.A. Hydromagnetic natural convective heat transfer flow in an isosceles triangular cavity filled with nanofluid using two-component nonhomogeneous model. International Journal of Thermal Sciences, 2016, 107, 272-288.
  28. Elshehabey, H.M. and Ahmed, S.E. MHD mixed convection in a lid-driven cavity filled by a nanofluid with sinusoidal temperature distribution on the both vertical walls using Buongiorno's nanofluid model. International Journal of Heat and Mass Transfer, 2015, 88, 181–202.
  29. Uddin, M.J., Rahman, M.M. and Alam, M.S. Analysis of natural convective heat transport in homocentric annuli containing nanofluids with an oriented magnetic field using nonhomogeneous dynamic model, Neural Computing and Applications, 2017. DOI 10.1007/s00521-017-2905-z.
  30. Zienkiewicz, O.C. and Taylor, R.L. The finite element method (4th Edition), McGraw-Hill, 1991.
  31. Al Kalbani, K.S. Alam, M.S. and Rahman, M.M. Finite element analysis of natural convective heat transfer flow of nanofluids inside a tilted square enclosure in the presence of oriented magnetic field. American Journal of Heat and Mass Transfer, 2016, 3(3), 186-224.