WP2 Establishing scale modelling rules for demersal trawls
We will establish scale modelling criteria for demersal trawls by comparing the geometries and forces acting on a full-scale gear and two scale models of it. We will achieve this by identifying an appropriate balance of the gravitational, drag, and contact forces. We know from before that these criteria will be a compromise and particular attention will be made to assessing their accuracy. This will be done using two scale model gears, which will be tested in the Flume Tank, and a full-scale gear, which will be tested during sea trails on DTU Aqua’s vessel, Havfisken. Fishing gear geometry and force measurements will be made using a range of underwater instruments (load cells, tension meters, acoustic spread meters, etc). The resulting criteria will generalise those that are being used at present, which do not account for bottom contact forces, and are really only suitable for pelagic gears. Hence, they will be a major advance in our ability to design and develop low impact demersal trawls.
This work package is led by SINTEF Ocean.