Hydraulic Modeling of a V-Shaped Fish Screen

An interesting project using a SonTek/YSI Acoustic Doppler Velocimeter (ADV) is being developed at Washington State University (WSU) under the direction of Dr. Thanos Papanicolaou and Research Assistant Adam Maxwell. The purpose of this project is to design the first vee-shaped bypass inlet ever to be used in conjunction with a rotary-drum fish screen.

This structure will be located on the Salmon River near Challis, Idaho. Consideration must be given to the design of this structure such that it will not be detrimental to the fish that pass through it. To accomplish this, several configurations need to be studied. There will be four different configurations with six tests run on each configuration. Through these tests, the ideal placement of the training wall, a structure that divides the flow upstream of the bypass, will be determined.

The ADV will be used to determine water velocity immediately upstream of the rotating drums, which must be 0.4 ft/s or less to avoid high mortality rates for the fish. These tests will be conducted at Albrook Hydraulic Laboratory on the campus of WSU using a 45.45% scale model of a "fishing pool" fabricated by the Idaho Department of Fish and Game in conjunction with the facilities and equipment already present at the laboratory.

		Figure 1 shows a top view of the fishing pool with the ADV ready to take measurements (arrow points to the ADV's probe).
		Figure 2 shows how data from the ADV was used to map or depict velocity isovels within the pool. The graph shows the velocity isovels from a top view of a submerged jet coming out of a fish passage orifice to the pool. The jet is asymmetric as the isovels indicate. The maximum velocity is attained at the center of the jet.
		Figure 3 shows the velocity vector in a 3D view of the flume. The length of the vectors is analogous to the magnitude of the velocity at different points within the pool. This plot indicates the recirculation patterns within the pool and provides useful information about the fish resting areas within the pool.

• ADV