Effect of panel shape on hydrodynamic performances of vertical v-shaped double- slotted cambered otter-board

摘要

The effect of panel shape on hydrodynamic performances of a vertical v-shaped double-slotted cambered otter-board was investigated using engineering models in a wind tunnel. Three different shape panels (rhomboid, left trapezoid and isosceles trapezoid) were evaluated at a wind speed of 28 m/s. Parameters measured included: drag coefficient C_(x), lift coefficient C_(y), pitch moment coefficient C_(m), center of pressure coefficient C_(p), over a range of angle of attack (0° to 70°). These coefficients were used in analyzing the differences in the performance among the three otter-board models. Results showed that the maximum lift coefficient C_(y)of the otter-board model with the isosceles trapezoid shape panels was highest (2.103 at α=45°). The maximum C_(y)/C_(x)of the otter-board with the rhomboid shape panels was highest (3.976 at α=15°). A comparative analysis of C_(m)and C_(p)showed that the stability of otter-board model with the isosceles trapezoid shape panels is better in pitch, and the stability of otter-board model with the left trapezoid shape panels is better in roll. The findings of this study can offer useful reference data for the structural optimization of otter-boards for trawling.