This flume tank is located at Nordsøen Forskerpark in Hirtshals, Denmark, where DTU Aqua has some of their offices and conducted these experiments. The flume tank used to be operated by SINTEF Ocean, but since 2023 Flume Tank North Sea A/S is responsible for its operations.
In the flume tank small and model fishing gear can be tested using water currents to assess the hydrodynamic properties, and the rolling conveyor belt bottom can be used to test the ground gear. On the 18th and 19th December 2023, we conducted flume tank experiments to investigate the effects on bottom trawl contact forces of the mass of the ground gear, the material friction, and the conveyor belt speed. In total, there were 72 different combinations of these variables.
On the 22nd to 26th January 2024 we conducted flume tank experiments to examine the effect of ground gear weight and conveyor belt speed on two different scale models, 1:10 and 1:5, of a demersal trawl. By varying these variables across 80 experimental scenarios, we aim to quantify their impact on fishing gear contact forces at different model scales.
On the 1st to 8th May 2024 full-scale sea trials were conducted on board DTU Aqua’s research vessel Havfisken to validate the findings from previous flume tank experiments. During these trials, three types of ground gear were tested on four different seabed types (firm sand, soft sand, sandy mud, and mud) and at three different towing speeds.
We look forward to analysing the results!
Text and images by Nurul Huda, DTU Aqua.
