Experimental Study of Geometrical Characteristics of Free and Boundary-Affected 30° Inclined Dense Jets in Unstratified Stagnant Environments

Submerged outfalls by discharging buoyant jets in the depth of seawater are widely used for the disposal of various types of effluents into the marine environment. A 60° inclined jet to the horizontal is accepted as the optimal angle of inclination for dense flow, but this angle is comparatively problematic for shallow waters; hence smaller inclination is preferred. The present paper investigates the geometrical characteristics of free (far from boundaries) and boundary-affected 30° inclined dense jets in unstratified stagnant ambient using laser-induced fluorescence technique. The major geometrical characteristics, including the centerline trajectory, centerline peak, terminal rise height, and horizontal location of return point, were analyzed by normalized data and plots. The free jets generally follow trends in previous experimental studies. It was observed that a dramatic reduction in the bed proximity parameter results in an asymmetry in the centerline trajectory and a decrease in the horizontal distance of the return point.