Numerical investigation of the effect of perforation inclination angle on the performance of a perforated pin-fin heatsink using two-phase mixture model

The numerical analysis of water/silver nanofluid (NF) flow in a perforated pin-fin heatsink (PFHS) is performed considering the nanoparticle concentration (φ) of 1% and seven different perforation inclination angles (γ). The configuration with the best hydrothermal performance and the lowest entropy generation rate at different values of Reynolds number ( Re ) is determined using the two-phase mixture technique. According to the results, the γs of 45º and -45º exhibit the highest heat transfer coefficient ( h ) and the lowest thermal resistance factor and mean CPU temperature at four studied Re s of 500, 1000, 1500, and 2000. Consequently, the highest hydrothermal performance evaluation criterion ( PEC ) was obtained for the heatsink with γ of 45º followed by γ of -45º at Re of 500; the increase in Re reduced the PEC due to the pressure drop. PEC of the heatsink with γ of 45º was almost 11.06–16.63% higher than that with γ of 0º. In addition, γ of -15º and 45º provided the lowest frictional and thermal entropy generation rates ( S˙fr and S˙th ) at Re of 1500 and then 2000. S˙fr and S˙th for γ of 45º were 1401% and 97% lower than those for γ of 0º at Re =1500.