水噴流の側壁付着現象
付着噴流の速度分布
1974 年 10 巻 5 号 p. 611-616
詳細
1974 年 10 巻 5 号 p. 611-616
The velocity profile 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 (=control nozzle width be): 25mm, offset D: 2.5 bm, side wall angle α: 15° and aspect ratio: 5.0.
Using water of about 20°C as the operating fluid, the studies were performed in the conditions of main jet velocity vo=2.5m/s and dimensionless control flow rate Qc/Qm=0∼0.3. The data were analyzed referring to Goertler's model of a turbulent jet.
The conclusions from the experimental study are:
1) The velocity decay along the attached jet center line is remarkable at the region downstream from the vortex where it is affected by the side wall.
2) The velocity profile perpendicular to the jet center line is closely approximated by Goertler's model in which a reasonable spread parameter iss evaluated separatel on the attached and unattached sides of the jet.
3) On the unattached side of the attached jet the spread parameter is constant, but on the attached side the parameter is a function of s, which is the co-ordinate along the jet center line.
