Between Dec 19, 2024 and Jan 2, 2025, datasets can be submitted to DRUM but will not be processed until after the break. Staff will not be available to answer email during this period, and will not be able to provide DOIs until after Jan 2. If you are in need of a DOI during this period, consider Dryad or OpenICPSR. Submission responses to the UDC may also be delayed during this time.

Browsing by Author "Ainsworth, Bruce"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Headrace Design Studies for the Jim Falls Hydro-Redevelopment Project
    (St. Anthony Falls Laboratory, 1987-08) Stefan, Heinz G.; Voigt, Richard L. Jr.; Lindblom, Karen L. C.; Ainsworth, Bruce; Colgan, Patrick
    The 48 MW Jim Falls Hydropower Redevelopment project on the Chippewa River, Wisconsin, required extensive model studies to facilitate the debris sluicing and to prevent intermittent vortex formation in front of the powerhouse intake. Debris, consisting mainly of natural materials from a forested and agricultural watershed, had to be directed to a gated spillway adjacent to the powerhouse (Fig. 1). To accomplish that goal, the surface circulation in the headwater pool had to be reversed. Vortices formed preferentially at two locations near the ends of the powerhouse, and were highly unstable in space and time. The highly irregular headrace geometry, in terms of width and depth, was found to be the cause of the undesirable flow features. A series of headrace modifications resulting in a more symmetrical approach channel configuration provided a debris flow pattern away from the powerhouse intake, and reduced frequency and strength of vortex formation to acceptable levels. A description of effective and ineffective design changes will be given.