Numerical analysis of thermal hydraulic performance of Al2O3-H2O nanofluid flowing through a protrusion obstacles square mini channel

In this study, numerical investigation has been carried out for a range of system and operating parameters in order to analyze the effect of protrusion obstacles on heat and fluid flow characteristics of nanopartical Al2O3 with concentration 4.0% and diameter 30 nm in square mini channel. The square mini channel has, stream wise spacing (Xs/dp) range of 1.4-2.6, span wise spacing (Ys/dp) range of 1.4-2.6, ratio of protrusion height to print diameter (ep/dp) of 1.67 and Reynolds number (Ren) ranges from 4000 to 18,000. Simulations were carried out to obtain heat and fluid flow behaviour of smooth and rough tube, using commercial CFD software, ANSYS 16.0 (Fluent). Renormalization k−ε model was employed to assess the influence of protrusion on turbulent flow and velocity field. Simulation results show that, the enhancement of 3.73 times in heat transfer and 4.25 times enhancement in pressure drop as a function of Xs/dp and Ys/dp of 1.8 respectively.