  This paper shows the CFD investigation of pressure drop and thermal
performance of aluminum oxide nano fluid inside square channel inserted a
cylinder with and without fin using two-phase method. The constant heat flux on
outer wall and laminar flow regime are applied in the considered domain using
finite volume method. The results depict that the enhance of nano-particles
volume concentration and Reynolds number have dramatic effects on heat transfer
coefficient enhancement. Moreover, the increase of nano-particle diameter has
opposite impact on heat transfer efficiency. The passive way leads to higher
pressure drops. For all fluids under consideration, pressure drop escalated
with Reynolds number. Injecting nano-particles into the water causes to
increase in pressure drop and this impact is more significant in high
nano-particle volume fraction.
