On the hydrodynamic resistance and stabilization of the coonstripe shrimp pot to reduce catch of a small size shrimp

Abstract

For the optimal design of a shrimp pot to control the catch size and to reduce catch the small size shrimp , tank experiments were carried out to study the pot stability under water . Tank experiments were carried out to measure the drag with 4 kinds of model pots that have 50% selection on the individual of 25 mm carapace length . The drag of each pot was measured every 10 times with changing the current speeds from 0.1 m/s to 0.7 m/s in 0.1 m/s intervals and the pot attack angle from 0。to 90 。in 15 。interval in a flume tank . The relation between the current speed and drag was presented . The stability of pot was estimated using the drag data and the friction data of Kim et al . (2008 b). The results showed that , the drag was shown lower as small as the projected area of pot depending on the current speeds and angles . The model pots were showed to slide on the seabed in case of rock at the current speeds 0.35 -0.38 m/s and the possibility of turn over at the current speeds 0.77 -0.89 m/s. In conclusion , the stability of a shrimp pot showed more stable as the pot of the lower the height and the smaller projected area on current .