Planning of special structures

Planning of special structures, e.g. attraction current pump

We are also planning attraction current pumps which generate a high flow with a low water content from the upper water of a power plant in the entry area of ​​a fish ladder. We take over here:

  • Submission planning and design of the attraction current pump
  • Detailed planning of the Venturi channel and nozzle line
  • Product deliveries
  • Construction supervision

Principle of the attraction current pump

The disadvantage of the previously widespread methods of increasing the attracting current is eliminated with this method by increasing the outflow from the fish pass not only by water from the upper water, but also by a flow from the underwater. The task is to promote a flow over a low head from the turbine underwater into the outlet area of ​​the fish pass. For this purpose, a simple water jet water pump can be used, but it is ideally suited for this task and draws its jet water from the headwater.

A free jet is generated in front of a cross-sectional constriction similar to a Venturi nozzle, the impulse of which is transmitted to the surrounding water. The flow velocity produced by it ensures in a narrow cross-section that the fish do not swim through in the wrong direction. The gradual widening leads to a rapid decrease in speed and also increases the delivery rate and the “efficiency” of this attraction pump.