Numerical study of natural convection heat transfer of Al2 O3/Water nanofluid in a Γ-shaped microchannel

Document Type: Research Paper


1 Department of Mechanical Engineering, Bu-Ali Sina University, Hamedan, Iran

2 Department of Mechanical Engineering, Shahrekord University, Shahrekord, Iran


Finite-volume procedure is presented for solving the natural convection of the laminar  nanofluid flow in a Γ shaped microchannel in this article. Modified Navier-Stokes equations for nanofluids are the basic equations for this problem. Slip flow region, including the effects of velocity slip and temperature jump at the wall, are the main characteristics of flow in the slip flow region. Steady state equations were solved by using time marching method. In provided FORTRAN code, the finite volume method and an explicit fourth-order Runge–Kutta integration algorithm were applied to find the steady state solutions. Also an artificial compressibility technique was used to couple the continuity to the momentum equations as it is simpler and converges faster. The Grashof numbers from  to  were considered. The results showed that Nusselt number increases with the Grashof number and the parameter R (the ratio of minimum diameter of nanoparticles and maximum one).. As the parameter R increases, the distortion of the isotherm lines increases to some extent.


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