Investigations of flow structures and performances of heat transfer in semi-circular grooved ducts by applying field synergy principal analysis: An experimental and numerical study

• DOI: 10.1016/j.icheatmasstransfer.2023.106801
• Publication Date: 2023-04-22T20:20:34Z
• Authors: Nehir Tokgoz; Mehmet Tahir Erdinç; Önder Kaşka; Besir Sahin
• Keywords: 01 natural sciences; 0104 chemical sciences

The present study aimed at investigating the flow structure and heat transfer mechanism through the corrugated channel experimentally and numerically. Particle imaging velocimetry (PIV), which can give detailed information about the wake and shear flow regions, was used for the experiments. The experimental and numerical works were performed considering Reynolds numbers in the range of 6 x 103 <= Re <= 12 x 103 and 3 x 103 <= Re <= 2 x 104, respectively. In the numerical part, aspect ratios (R/hp) of examined grooves have been chosen as 0.1, 0.2, and 0.3, and for the experiment, only one aspect ratio was chosen which was 0.3. The experimental studies were conducted regarding different Reynolds numbers as well as the distributions of instantaneous and timeaveraged velocity contours, Turbulence Kinetic Energy, Reynolds shear stress, and vorticity. The standard SST k-omega turbulent method was employed for the case of numerical study to predict the thermal performance (eta) along with Nusselt numbers (Nu) the friction factors (f) and local field synergy angles (alpha, beta) were calculated. As a result, the Nusselt number (Nu) values of the corrugated channels were higher than the parallel plate, and the increment in the Nusselt number initially increased and later decreased with Reynolds numbers for all aspect ratios considered.