Computational analysis of nanofluid effects on convective heat transfer enhancement of micro-pin-fin heat sinks

Abstract

Numerical investigation on the application of nanofluids in Micro-Pin-Fin Heat Sinks (MPFHSs) has been presented in this paper. To investigate flow and heat transfer behavior in MPFHS the three-dimensional steady Navier–Stokes and energy equations were discretized using a finite volume approach and have been solved iteratively, using the SIMPLE algorithm. DI-water is used as a base coolant fluid while the nanoparticles used in the present study are CuO nanoparticles with mean diameters of 28.6 and 29nm and Al2O3 nanoparticles with mean diameters of 38.4 and 47nm. The results show that (i) a significant enhancement of heat transfer in the MPFHS due to suspension of CuO orAl2O3 nanoparticles in the base fluid in comparison with pure water, (ii) enhancement of heat transfer is intensified with increasing volume fraction of nanoparticles and Reynolds number, (iii) increasing volume fraction of nanoparticles which is responsible for higher heat transfer performance leads to higher pressure drop or Euler number in MPFHS but the enhancements are small, especially for lower particle volume fractions, (iv) with decreasing particle diameters the Nusselt number increases for Al2O3–water nanofluid while the trend is reverse for CuO–water nanofluid.