Effect of Dimpled Rib with Arc Pattern on Hydrothermal Characteristics of Al2O3-H2O Nanofluid Flow in a Square Duct: Fid-Bau Portal

Effect of Dimpled Rib with Arc Pattern on Hydrothermal Characteristics of Al₂O₃-H₂O Nanofluid Flow in a Square Duct

Anil Kumar / Rajesh Maithani / Sachin Sharma / Sunil Kumar / Mohsen Sharifpur / Tabish Alam / Naveen Kumar Gupta / Sayed M. Eldin

Abstract

The present work is concerned with the experimental analysis of the thermal and hydraulic performance of $A l_{2} O_{3} - H_{2} O$ nanofluid flow in dimpled rib with arc pattern in a square duct. The Alumina nanofluid consists of nanoparticles having a size of 30 nm. Reynolds number $(R e_{n u m})$ studied in the square duct range from 5000 to 26,000. The nanoparticle volume fraction ( $ϕ_{n p})$ ranges from 1.5% to 4.5%, the ratio of dimpled-arc-rib-height to print-diameter $(H_{A D} / P_{d})$ ranges from 0.533 to 1.133, the ratio of the dimpled-rib-pitch to rib height $(P_{A D} / H_{A D})$ range from 3.71 to 6.71 and dimpled arc angle ( $α_{A D})$ range from 35° to 65°. The $A l_{2} O_{3} - H_{2} O$ -based nanofluid flow values of Nusselt number $(N u_{r s})$ and friction factor $(f_{r s})$ are higher in comparison to pure water. The dimpled ribs in the arc pattern significantly improved the thermal-hydraulic performance of the investigated test section. The nanoparticle concentration of 4.5%, the ratio of dimpled arc rib height to print diameter of 0.933, the relative dimpled arc rib height of 4.64 and the dimpled arc angle of 55° deliver the maximum magnitude of the heat transfer rate. The maximum value of the thermal-hydraulic performance parameters was found to be 1.23 for $A l_{2} O_{3} - H_{2} O$ -based nanofluid flow in a dimpled rib with arc pattern square duct for the range of parameters investigated. Correlations of $N u_{r s}, f_{r s} and η_{r s}$ have been developed for the selected range of operating and geometric parameters.