Location
UMass Amherst
Start Date
27-6-2011 2:35 PM
End Date
27-6-2011 2:55 PM
Description
The Alaska Steeppass is a type of chute fishway used extensively on coastal streams in the east and in remote locations throughout the country. Typically prefabricated out of 1/4" aluminum plate into 27-inch-high, 18-inch-wide, 10-foot sections, these chutes have the advantage of being highly portable and relatively inexpensive. The Model "A" Steeppass, a derivative of the modified Denil No. 6 developed by McLeod and Nemenyi, is the most widely used variant because of its ability to reduce flow velocities to magnitudes negotiable by many salmonid and alosa species. Efforts to quantify the energetic costs required for migrants to swim up these chutes have been minimal. The challenges to this problem are manifold; the 3D flow fields in a Steeppass are not well known and the energetic costs are a function of these complex flow fields and the mechanics of fish propulsion. However, Webb (1975), Belke (1991) and others have proposed simplified methods for quantifying the drag forces on fish using the principles of fluid mechanics. by integrating the drag force along a passage path line, work energy (i.e., energetic cost) can be estimated. This presentation will review those methods and apply them to the hydraulics of a Model A Steeppass fishway using USFWS- recommended rating curves. The results may provide engineers and biologists with insight into the relative energetic costs of fish ascending chute passes. Moreover, this work serves as a springboard for an ongoing effort to develop a 3D computational hydraulic model of Steeppass flow fields and, in turn, a more rigorous solution to the energetic costs for fish passage.
Session A2- Simple drag force and energy calculations for fish passage through a model a steeppass
UMass Amherst
The Alaska Steeppass is a type of chute fishway used extensively on coastal streams in the east and in remote locations throughout the country. Typically prefabricated out of 1/4" aluminum plate into 27-inch-high, 18-inch-wide, 10-foot sections, these chutes have the advantage of being highly portable and relatively inexpensive. The Model "A" Steeppass, a derivative of the modified Denil No. 6 developed by McLeod and Nemenyi, is the most widely used variant because of its ability to reduce flow velocities to magnitudes negotiable by many salmonid and alosa species. Efforts to quantify the energetic costs required for migrants to swim up these chutes have been minimal. The challenges to this problem are manifold; the 3D flow fields in a Steeppass are not well known and the energetic costs are a function of these complex flow fields and the mechanics of fish propulsion. However, Webb (1975), Belke (1991) and others have proposed simplified methods for quantifying the drag forces on fish using the principles of fluid mechanics. by integrating the drag force along a passage path line, work energy (i.e., energetic cost) can be estimated. This presentation will review those methods and apply them to the hydraulics of a Model A Steeppass fishway using USFWS- recommended rating curves. The results may provide engineers and biologists with insight into the relative energetic costs of fish ascending chute passes. Moreover, this work serves as a springboard for an ongoing effort to develop a 3D computational hydraulic model of Steeppass flow fields and, in turn, a more rigorous solution to the energetic costs for fish passage.
Comments
Kathryn Plymesser received her undergraduate degree in Civil Engineering in 2001 from Case Western Reserve University in Cleveland, Ohio. After working as a consulting engineer in land development for six years, she decided to return to graduate school full-time. She is currently a PhD Candidate in the Civil Engineering Department (Water Resources) at Montana State University (MSU) and was recently hired into the Student Career Experience Program (SCEP) with the US Fish and Wildlife Service at the Region 5 headquarters in Hadley, MA. Her research work includes three-dimensional computational fluid dynamics modeling and fish passage energetics. She recently received a Benjamin PhD Fellowship and the Betty Coffey Graduate Award from the College of Engineering at MSU.