Trajectories of two side-by-side turbulent jets in a cross flow with different momentum ratios

The effects of 2 momentum ratios (r) of 3.3 and 6.6 on the trajectories of 2 side-by-side round turbulent wall jets in a cross flow were experimentally investigated. The jets were at 2d spacing in span wise direction and had the same momentum ratios. Here d is the jets' inside diameters. The Reynolds numbers based on jet diameter were 6,200 and 12,400. For r = 6.6, measurements of mean and 2 components of turbulent velocities were carried out at 6 different planes of x/d = 0.5, 1, 2, 5, 10.7, and 15.7 and compared with the corresponding results for r = 3.3. The results show that increasing the momentum ratio reduces the boundary layer effect on the trajectories in the near field with increased throw distance and rate of penetration. The jets are interacting more intensely with r = 6.6, resulting in increases in the turbulent velocity and primary turbulent shear stress.