Abstract
The velocity distribution of the attached jet in a liquid fluid amplifier has been investigated by means of a constant temperature hot-film anemometer. The dimensions of the fluidic element used are; main nozzle width bm: 10∼25mm (variable), offset D: (2.0∼6.1) bm (variable) and side wall angle α: 0∼22.5° (variable).
Using water of about 20°C as the operating fluid, the studies were performed in the conditions of main jet velocity υ0=2.5∼4.0m/s and various forms of the element. The data were analyzed referring to Goertler's model of turbulent jet.
The following results of the experimental studies are obtained: (1) The velocity distribution of any attached jet is closely approximated by Goertler's model in which a reasonable spread parameter is evaluated separately on the attached and unattached sides of the jet. (2) The effect of element in the conditions of various side wall angles, offsets and nozzle widths on the spread parameter was studied. (3) Empirical formulas for the spread parameter were obtained as functions of radius of curvature of jets. (4) In any attached jet, the momentum conservation holds good in the upstream region of the vortex.
