Jet Interaction in a Still Ambient Fluid

Interaction between a jet and its neighbors in a still ambient fluid is dealt with. A model for the merging of an infinite line of equally spaced identical jets in a still ambient fluid is developed. The velocity and tracer distributions in the model are determined based on the summation of momentum fluxes and tracer fluxes, respectively. Laser-induced fluorescence experiments are conducted for four different port spacings. Analysis of these and past experimental results show that individual jets spread asymmetrically during the merging process. The current model satisfactorily predicts the spreading rate changes in the free entrainment plane and the jet merging plane, as well as the tracer distributions during the merging process. Flapping motions were observed during jet merging, but these motions were not sufficiently persistent to significantly change the concentration fluctuations profiles.