Comparison between dynamic simulation and physical model testing of new trawl design for Chilean crustacean fisheries

A new bottom trawl was designed and evaluated for the crustacean fisheries of central Chile using both dynamic simulation and model testing methods. First, a dynamic simulation of the trawl was evaluated using DynamiT software. Second, for consistency and comparison purposes, a 1:5 scale model was built and tested in a flume tank at Memorial University of Newfoundland (Canada). The comparison is used to verify whether design results comply or not with load and geometry goals of the new trawl. The two methods showed consistent results. The new net has a total drag of less than 13,000 N at 2 knots of towing speed, a headline height at the mouth greater than 1.8 m, an internal height in the forward section of the cod-end greater than 0.8 m and a wing-end spread greater than 15 m. We discuss the advantages of the methods used and the benefits of using them in a complementary way for the design of new trawl gears.