Abstract
This study investigates analytically the hydrodynamic and thermal behaviour of a fully developed natural convection flow in a vertical micro-porous-annulus (MPA) taking into account the velocity slip and temperature jump at the outer surface of inner porous cylinder and inner surface of outer porous cylinder. A closed — form solution is presented for velocity, temperature, volume flow rate, skin friction and rate of heat transfer expressed as a Nusselt number. The influence of each governing parameter on hydrodynamic and thermal behaviour is discussed with the aid of graphs. During the course of investigation, it is found that as suction/injection on the cylinder walls increases, the fluid velocity and temperature is enhanced. In addition, it is observed that wall surface curvature has a significant effect on flow and thermal characteristics.
Similar content being viewed by others
References
M. Gad-el-Hak, The fluid mechanics of microdevices, the Freeman scholar lecture, J. Fluids Engng, 1999, Vol. 121, P. 5–33.
H.C. Weng and C.K. Chen, Fully developed thermocreep-driven gas microflow, Appl. Phys. Lett., 2008, Vol. 92, No. 9, P. 094105-1–094105-6.
C.K. Chen and H.C. Weng, Natural convection in a vertical microchannel, J. Heat Transfer, 2005. Vol. 127, P. 1053–1056.
B.K. Jha, B. Aina, and S.B. Joseph, Natural convection flow in a vertical microchannel with suction/injection, J. Process Mech. Engng, DOI: 10.1177/0954408913492719.
A.F. Khadrawi, A. Othman, and M.A. Al-Nimr, Transient free convection gas flow in a vertical microchannel as described by the hyperbolic heat conduction model, Int. J. Thermophysics, 2005, Vol. 26, No. 3, P. 905–918.
A. Khadrawi and M.A. Al-Nimr, Unsteady natural convection fluid flow in a vertical microchannel under the effect of the Dual-Phase-Lag heat conduction model, Int. J. Thermophysics, 2007, Vol. 28, No. 4, P. 1387–1400.
O.M. Haddad, M.M. Abuzaid, and M.A. Al-Nimr, Developing free-convection gas flow in a vertical openended microchannel filled with porous media, Numer. Heat Transf. A, 2005, Vol. 26, No. 3, P. 905–918.
L. Biswal, S. Som, and S. Chakraborty, Effects of entrance region transport processes on free convection slip flow in vertical microchannel with isothermally heated walls, Int. J. Heat Mass Transfer, 2007, Vol. 50, No. 7–8, P. 1248–1254.
C.K. Chen and H.C. Weng, Developing natural convection with thermal creep in a vertical microchannel, J. Phys. D, 2006, Vol. 39, No. 14, P. 3107–3118.
M. Avci and O. Aydin, Mixed convection in a vertical parallel plate microchannel, J. Heat Transfer, 2007, Vol. 129, No. 2, P. 162–166.
M. Avci and O. Aydin, Mixed convection in a vertical parallel plate microchannel with asymmetric wall heat fluxes, J. Heat Transfer, 2007, Vol. 129, No. 8, P. 1091–1095.
M. Avci and O. Aydin, Mixed convection in a vertical microannulus between two concentric microtubes, J. Heat Transfer, 2009, Vol. 131, No. 1, P. 014502–014505.
H.C. Weng and C.K. Chen, Drag reduction and heat transfer enhancement over a heated wall of a vertical annular microchannel, Int. J. Heat Mass Transfer, 2009, Vol. 52, P. 1075–1079.
M.A. Chaudhary and J.H. Merkin, The effect of blowing and suction on free convection boundary layers on vertical surfaces with prescribed heat flux, J. Engng Math., 1993, Vol. 27, P. 265–292.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jha, B.K., Aina, B. & Muhammad, S.A. Combined effects of suction/injection and wall surface curvature on natural convection flow in a vertical micro-porous annulus. Thermophys. Aeromech. 22, 217–228 (2015). https://doi.org/10.1134/S0869864315020080
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0869864315020080