Numerical study on nanofluid flow through heat exchanger with perforations conical rings

Heat exchangers use perforated conical rings (PCRs) as turbulence-promoters/ turbulators to enhance heat transfer rates. In the present study. A comparison has been made between the flow analysis of nanofluids within perforated conical rings with uniform hole sizes and those with non-uniform hole sizes at constant wall temperature conditions. The perforated conical rings have eight holes and a pitch ratio of ۴. An Al۲O۳-Water nanofluid with a diameter of ۱% has been used as the working fluid, with Reynolds numbers ranging from ۵۰۰۰ to ۱۴۰۰۰ indicating a fully turbulent flow regime. According to this study, the Nusselt numbers of conical rings with holes of different sizes are higher and the friction factors are lower than that of conical rings with the same size holes. PCRs were rotated and holes of various diameters were positioned in the same direction in the second part of the study. This resulted in a lower friction factor and high Nusselt number.