Hydrodynamic Model of Ash Meadows Fish Conservation Facility

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The US Fish and Wildlife Service���s Ash Meadows Fish Conservation Facility (FCF) was designed to replicate the natural conditions occurring in Devils Hole. The 100,000 gallon tank contains a reconstruction of the shallow shelf of Devils Hole, and the spatial orientation of the tank is similar to that of Devils Hole. Louvered shutters in the facility roof make it possible to control the solar exposure to match that of Devils Hole, and the water temperature and water chemistry in the refuge tank can be controlled by the facility���s software system and mechanical room. The facility is currently operated to mimic the pre-development conditions of Devils Hole, but with the water temperature and oxygen levels providing a slightly friendlier environment for spawning and recruitment. The controls at the FCF are able to maintain specific physical and chemical parameters, and a recirculating system ensures that these conditions are uniform throughout the tank. The controls, however, do not replicate the movement and circulation of water seen in Devils Hole. In Devils Hole, this movement is caused by a number of factors, including wind and tidal influence, but the primary driver of circulation is thermal gradients in the water column. Using a computational fluid dynamics (CFD) software package (FLUENT), Hausner et al. (2013) were able to simulate circulation in Devils Hole with an energy-driven model. In this project, I propose to create an analogous CFD model of the FCF tank and compare the circulation patterns in the FCF to simulations of natural circulation in Devils Hole.

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