Reattachment Phenomena and Diffusion of Plane Submerged Water Jets.

Plane Offset Jet Discharged into Water of Finite Depth

“…As mentioned earlier, because the jet can deflect to either boundary in this bistable region, these data were obtained by repeating experiments several times until a deflection to the solid boundary or the free boundary was realized. The solid line shows the experimental result obtained by Sudo et al (5) with which our data agree relatively well. It can be seen that there is no clear difference in x R between the reattachment to the free boundary and that to the solid boundary.…”

“…Although several studies have been reported on an air jet between two solid walls, mainly in view of the development of a fluidic device (4) , very little has been reported concerning a submerged wa-ter jet above an adjacent wall. Sudo et al (5) examined experimentally the behavior of the plane submerged water jet. Although they succeeded in showing that the flow field could be classified into several patterns depending on two parameters, namely, the offset height from the bottom wall and the Froude number, their results mainly relied on flow visualization, and detailed measurements of the velocity field were not conducted.…”

Deflection of jets discharged into a reservoir with a free surface

“…Similar diagrams with figures 12(a) and (b) were obtained in experiments by Sudo et al (1998), Shimada et al (2004) and Tsunoda et al (2006) although their experiments were performed at much larger Reynolds numbers such as Re = 4430-177 00 (Sudo et al 1998, Shimada et al 2004 and Re = 2500 (Tsunoda et al 2006) and the length of the channel (L in figure 1) was much longer. They concluded that the direction of deflection of the flow is determined solely by the values of h 1 and h 2 , independently of the Reynolds number, and they attributed the mechanism of deflection to the Coanda effect.…”

“…It has been long thought that the deflection of jets issuing at a middle height is uniquely determined by the configuration of the reservoir. However, Sudo et al (1998) and Shimada et al (2004) found in their experiments that a planar submerged water jet discharged into a reservoir with a free surface deflects towards either of the two boundaries, which was confirmed by Tsunoda et al (2006). The two kinds of deflected flow are realized in a range of the depth and the height of the inlet throat or nozzle, while the flow always deflects either to the free surface or to the bottom in the two extreme conditions where the throat is close to the free surface or to the bottom, respectively.…”