Abstract:

The interaction of mutually perpendicular submerged turbulent water jets is studied from the measurement of the enhanced hydrodynamic near-field pressure spectrum. One jet is a conventional single-phase, free turbulent shear flow circular jet, while the other jet is a two-phase bubbly jet of similar construction. The overlap region is located at four-nozzle diameters (4D) away from each orifice. A small hydrophone located outside the overlap region (4D away from the interaction region and 45 deg from the jet axis) measures the near-field pressure spectrum. Very small gas bubbles are required for this two-phase turbulent jet. They are generated by pressurized carbonated water flowing through a thin circular nozzle plate having an array of small holes. These CO[inf 2] gas bubbles are mixed within the entrance to the tapered jet nozzle. Alternatively, bubbles are generated by pressurized N[inf 2] gas passing through a fritted disk housed in a Buchner funnel located near the nozzle entrance. Spectra are measured and compared for different void fractions and different Reynolds numbers that are based on the jet diameter.