Author(s): Baafour Nyantekyi-Kwakye; Mark F. Tachie; Shawn P. Clark; Jarrod Malenchak; Getnet Y. Muluye

Linked Author(s): Mark Tachie, Shawn Clark, jmalenchak

Keywords: Offset jet; particle image velocimetry; proper orthogonal decomposition; reattached flows; Reynolds stress; two-point correlation

Abstract: Three-dimensional turbulent offset jets were investigated using a particle image velocimetry technique. Detailed measurements were performed for offset height ratios of 0, 2 and 4. The presence of backflow influenced the distribution of the mean velocity and Reynolds stresses. A two-point correlation analysis was used to investigate the spatial distribution of large-scale structures within the inner shear layer of the flow domain. The results revealed that large-scale structures dominate the inner layer of the self-similarity region. Proper orthogonal decomposition was performed on the fluctuating velocity field within the symmetry and lateral planes using the snapshot approach. Results from the reconstructed field provided insight into the contributions of the most energetic structures to the turbulence statistics. The energetic structures contributed more to the Reynolds shear stress and streamwise turbulence intensity, while contributing less to the wall-normal turbulence intensity.

DOI: https://doi.org/10.1080/00221686.2015.1076532

Year: 2015