Net Loft

Net Loft Net Loft

Contact Facility Operator(s) :

Centre for Sustainable Aquatic Resources (CSAR)   Contact Us

Facility Location : Ridge Road campus, St. John's

The development of fishing gears for the commercial fishing industry has changed dramatically over the last few decades. Today's modern designs are more advanced and sophisticated as a result of increasing fuel costs, the need for species- and size-selectivity, stringent bycatch restrictions, and the necessity to minimize impact on the environment.

Meeting these challenges has lead to significant improvements in the way new fishing gears are designed and tested. This includes advances in computer design, numerical simulation, physical modeling, flume tank capability, and direct observation using underwater cameras, acoustics, and trawl-mounted sensors.

The Centre offers numerical simulation capability using DynamiT software developed by IFREMER. The software has the ability to evaluate the hydrodynamic performance of virtually any trawl type. It is used by the research team to visualize the effect of certain materials and design features on trawl shape and performance under different rigging and towing scenarios.

The software is used to test the viability of design concepts prior to physical modelling and full-scale prototype evaluations. Performance testing of scale engineering models is conducted using the flume tank. Calculations are carried out using Froude scaling rules to ensure the results from the flume tank testing have validity for the full-scale fishing gear.

Choosing the appropriate scale (e.g., 1:3) requires finding a balance between the limitations of the test facility (i.e., flume tank size), objectives of the test program, ability to extrapolate model results to full-scale performance, and the ability to source components for the model.  In almost all cases, the majority of components have to be custom ordered or fabricated in-house.