Author : Vishal V. Dhole, V. S. Shinde and S. S. Kore

This paper explains the effect of change in perforation geometry and number of perforations of cylindrical pin fin heat sink on heat transfer rate and pressure drop. Heat sinks were tested in rectangular wind tunnel having internal cross section 50×100 mm2 . Pin fins were arranged in staged manner. Tests were conducted on different heat sinks at constant heat input of 60W and Reynolds Number 10000-30000. Conical perforations acts like convergent nozzles thus increases the velocity of air passing through them, increased velocity of air raises turbulence over heat sink. Effect of number of conical perforations is studied by changing number of conical perforations. It is found that increase in number of perforation reduces pressure drop and increases Nusselt number. Angle of conical perforations is also varied which plays important role in generating turbulence.

Keywords: turbulence, conical perforations, staggered arrangement, pressure drop, convergent nozzle.