立式V型曲面网板的水动力性能

Hydrodynamic characteristics of vertical V type otter board

采用正交优选法来考察网板板面折角、展弦比以及后退角对立式V型曲面网板水动力性能的影响。试验结果证明影响网板水动力性能的最重要的因素是网板板面折角,其次是展弦比和后退角。当网板的板面曲率为14%、板面折角为12°、展弦比为1.60、后退角为10°时,网板具有较高的水动力性能。当冲角为25°和28°时,网板的升力系数均为1.68。另外,通过对优选网板添加模拟海底的试验证明,网板在底层作业时,其临界冲角从28°减小为25°;在常用工作冲角范围内,网板在底层时的扩张性能要高于中层,同时,网板的升阻比也略有上升,并能在较宽的冲角范围内持续保持较高的扩张性能。

This study inspected the effects of main structure parameters of otter board on the hydrodynamic characteristics of vertical V type otter board by the orthogonal design and appending the simulated sea bottom, based on the test of model in the wind tunnel. The test results indicated as follows: 1. one of the most important factors to influence the hydrodynamic characteristics of otter board was dihedral angle, followed by aspect ratio and sweepback angle. When the curvature on surface of otter board is 14%, the dihedral angle of the optimal match was 12°, aspect ratio was 1.60 and sweepback angle was 10°. The lift coefficient was 1.68 and higher than tested other boards when attack angle was 25° and 28°. 2. the critical angle of attack of the optimized otter board is reduced from 28° to 25° after appending the simulated sea bottom. It was obvious that the attack angle of vertical V type otter board on bottom was less than that in middle water. 3. the lift coefficient of the optimized otter board was obviously raised in the range of the commonly used attack angle after appending the simulated sea bottom. Meanwhile the lift to drag ratio also rose slightly. However, the lift to drag ratio held the line at attack angle of 20°. 4. in the front of the critical attack angle the moment coefficient of the optimized otter board rose slightly after appending the simulated sea bottom and it was favorable for the stabilization of otter board in practical operation.