网口部分网衣结构对帆式张网性能的影响

通过对帆式我模型水池试验，研究了帆式张网网中部分网衣结构对网具性能的影响。试验表明：（１）背腹网网口网农弧形剪后，背腹网网衣受力均匀程度明显改善，网具阻力平均下降３．５％，网口垂直扩张平均增加４．７％，水平扩张平均增加７．２％。（２）背腹、侧网网口网衣剪成弧形后，网具阻力平均下降２４．２％。水平扩张低速时有所下降，但高速时开始增加，平均增幅为３．５％，侧网网口网衣弧形剪对网口垂直扩张影响不大。

EFFECT OF STRUCTURE IN NET MOUTH PART ON PERFORMANCE OF CANVAS-SPREADING STOW NET

Research on effect of structure of the net mouth of strow net with canvas spreader on net performance was carried out and discussed in this paper, through model testing in towing tank. The test showed: 1.By curve cutting in the top and bottom parts of the net mouth, net drag decreased by 3. 9% averagely,vertical opening and horizontal spreading averagely increased by 4. 7% and 7. 2% respectively. 2. Through curve cutting in the top, bottom and side parts of the net mouth, net drag decreased by 24. 2% averagely, horizontal spreading went down slightly at low current speed but increased at higher current speed. Curve cutting in side parts of net mouth had little effect on vertical opening.