Experimental Heat Transfer, Vol.28, No.4, 354-365, 2015
INVESTIGATION OF THERMAL PERFORMANCE OF PERFORATED FINNED HEAT EXCHANGERS
In this study, the thermal performance of perforated finned heat exchangers with angle of rotation theta was experimentally investigated. Six-millimeter-diameter holes that were opened on each circular fin on a heating tube have a potential to reduce the thickness of the boundary layer that is formed on the circular fins placed on the heating tube, thus increasing heat transfer through convection in this area. The experiments were carried out at six different angular locations to determine the best angular location. In addition, a perforated finned heater was compared with an imperforate finned heater. For the finned heater at 60 degrees, the effectiveness is 18% higher and the pressure drop is 1.16% lower than other angular positions. In this respect, it can be concluded that the best angular position is 60 degrees. In addition, results show an increase in effectiveness with an increasing number of transfer units.