1Shimonoseki Research Institute, Nichimo Co., Ltd., Shimonoseki, Yamaguchi 750-1136, 2Faculty of Marine Science, Tokyo University of Marine Science and Technology, Minato, Tokyo 108-8477, Japan
The hydrodynamic characteristics of minnow netting composed of high-strength polyethylene (Dyneema) with different types of twine diameter and mesh size were evaluated through experiments conducted in a flume tank. The drag coefficient CD90 of Dyneema minnow netting set normal to the water flow was 8% and 25% smaller than that of minnow netting made of the conventional materials of polyamide and polyvinyl alcohol, respectively. The drag coefficient CD0 of minnow netting set parallel to the water flow showed a slight difference between the materials. Additionally, CD90 and CD0 were expressed as functions of Reynolds number and mesh factor α. Furthermore, the drag and lift coefficients of minnow netting set at various angles to the water flow were estimated by empirical equations as functions of CD90, CD0 and attack angle θ.