Visualization of secondary flow development in high aspect ratio channels with curvature

Investigation of Transcritical Methane Flow and Heat Transfer in Curved Cooling Channels

“…In the past many researchers argued about the effect of cross-section aspect ratio on the vortex pattern and the resulting heat transfer in the case of curvature. 11,16,17 In fact, the possible occurrence of vortex breaking due to the narrow section of the HARCC would result in a less effective fluid mixing and thus poor cooling performances with respect to low aspect ratio cooling channel. However, for the application of interest, experimental studies have shown that aspect ratio has little impact on the curvature heat transfer enhancement; 15 in fact, evidence of strong recirculation in HARCC with no vortex breaking has been observed.…”