PNNL-13501 - Pacific Northwest National Laboratory

Results and Accomplishments
We developed and applied mathematical models capable
of simulating the hydrodynamic flow field and fish
behavior near large hydroelectric projects by applying
two hydrodynamic models. One model, Flow3D, is
capable of simulating free-surface flows, which are of
critical importance near high flow outfalls. The other
model, STAR-CD, is capable of easily simulating the
complex hydroelectric dam structure as well as
complicated bathymetry. By applying both of the models,
a complete hydrodynamic description of the entire
hydroelectric project was achieved.
Results from STAR-CD were then used as the driving
flow field in NWGrid. NWGrid then simulated the paths
of particles introduced into the flow. Particle paths were
modified using statistical processes to coarsely simulate
fish behavior. Simulation of actual fish behavior, driven
by external (non-hydrodynamic) forces, is an ongoing
research effort, and a complete description in NWGrid is
beyond the scope of this project. It is anticipated,
however, that by continuing research in this area, a
continued blend of modeling hydrodynamic forces and
fish behavior will produce management tools capable of
predicting the most beneficial solution to these types of
problems.
Summary and Conclusions
Two, three-dimensional hydrodynamic models were
applied to simulate the turbulent hydrodynamic regime
downstream of a hydroelectric project. Results indicate
that these models are capable of simulating these
environments with a reasonable degree of confidence, as
compared to laboratory and field data.
A third model was applied to simulate fish movement.
Although behavioral methods used to simulate the fish
movement were simplistic, linkage of these three models
provides the first step toward the complete simulation of
fish response to hydrodynamic forces.
References
Gharangik AM and MH Chaudhry. 1991. “Numerical
simulation of hydraulic jump.” Journal of Hydraulic
Engineering, American Society of Civil Engineers,
117(9), September.
Rajaratnam N and MR Chamani. 1995. “Energy loss at
drops.” Journal of Hydraulic Research 33(3):373-384.
Computational Science and Engineering 129