Location
Groningen, The Netherlands
Event Website
http://fishpassage.umass.edu/
Start Date
22-6-2015 11:25 AM
End Date
22-6-2015 11:40 AM
Description
Abstract:
The vertical slot fishway is one of the most commonly used fish passage facilities in Germany. The flow conditions within fishway play an important role in the establishment of ecological connectivity, because they determine whether fish can pass, with regard of their given swimming performance.
Earlier studies have shown that two different types of flow patterns, separated by a transition area, may develop in the pools depending on the width-to-length (B/L) ratio of the pools and the slope of the fishway.
In order to gain insight in the formation of different flow patterns, an extensive study of different geometric parameters was performed, with a total of 60 different designs. Different pool geometries and slopes were installed in a physical model at Theodor-Rehbock-Laboratory of the Institute for Water and River Basin Management (IWG) in Karlsruhe. Flow patterns were recorded photo-optically by long time exposure, water depths were measured with an ultrasonic distance sensor and flow velocities by ADV. The measurements were analysed to obtain quantitative information about flow patterns, velocities, energy budget of the pools, relationship between discharge and flow depth and water level difference between adjacent pools. Unlike in previous studies, not only the B/L ratio but the entire pool geometry was varied in accordance to the German guidelines. Small slope ranges between 2.8 and 5 %, typical for Federal German waterways, were studied for the first time.
Both flow patterns could be observed under identical B/L and slope. The results show that parameters apart from the B/L ratio and slope are essential for determining the formation of flow patterns. Especially the variation of the slot angle had a large influence on the flow patterns. The flow velocity measurements show differences between the two flow patterns in terms of position and magnitude of maximum velocities in the pools.
Session D1: Experimental Study on Flow Patterns in Vertical Slot Fishways
Groningen, The Netherlands
Abstract:
The vertical slot fishway is one of the most commonly used fish passage facilities in Germany. The flow conditions within fishway play an important role in the establishment of ecological connectivity, because they determine whether fish can pass, with regard of their given swimming performance.
Earlier studies have shown that two different types of flow patterns, separated by a transition area, may develop in the pools depending on the width-to-length (B/L) ratio of the pools and the slope of the fishway.
In order to gain insight in the formation of different flow patterns, an extensive study of different geometric parameters was performed, with a total of 60 different designs. Different pool geometries and slopes were installed in a physical model at Theodor-Rehbock-Laboratory of the Institute for Water and River Basin Management (IWG) in Karlsruhe. Flow patterns were recorded photo-optically by long time exposure, water depths were measured with an ultrasonic distance sensor and flow velocities by ADV. The measurements were analysed to obtain quantitative information about flow patterns, velocities, energy budget of the pools, relationship between discharge and flow depth and water level difference between adjacent pools. Unlike in previous studies, not only the B/L ratio but the entire pool geometry was varied in accordance to the German guidelines. Small slope ranges between 2.8 and 5 %, typical for Federal German waterways, were studied for the first time.
Both flow patterns could be observed under identical B/L and slope. The results show that parameters apart from the B/L ratio and slope are essential for determining the formation of flow patterns. Especially the variation of the slot angle had a large influence on the flow patterns. The flow velocity measurements show differences between the two flow patterns in terms of position and magnitude of maximum velocities in the pools.
https://scholarworks.umass.edu/fishpassage_conference/2015/June22/40
Comments
Presenting Author Bio: Verena Höger is a hydraulic engineer and PhD student at the Institute for Water and River Basin Management (IWG) of the Karlsruhe Institute of Technology (KIT). After graduating at the Karlsruhe Institute of Technology (KIT) in 2012, she worked as a scientific assistant at the Federal Waterways Engineering and Research Institute of Germany. Her work focuses on physical modelling and laboratory studies of vertical slot fishways.