Experimental study of flow structures near the merging point of two parallel plane jets using PIV and POD

The initial and interacting region near the merging point of unventilated two parallel plane jets were investigated using Particle Image Velocimetry (PIV) and Proper Orthogonal Decomposition (POD). Two parallel rectangular nozzles with an aspect ratio of 15.1 (5.8 mm in width and 87.6 mm in length with 12 mm spacing) produced the jets at Re ≈ 4900 based on the jet width. This study collected statistically enough number of data with high spatiotemporal resolution. The experimental data was evaluated in terms of PIV uncertainty and statistical convergence. The POD analysis visualized the interaction and transportation of multi-scale vortical structures and their spectral characteristics. The experimental data also presented the characteristic parameters of the two parallel plane jets including the converging region and the location of the merging point. Two models to predict the merging point were proposed satisfying several experimental data reported.