Hydrodynamic characteristics of a hyper-lift otter board with wing-end plates

Shi

et al. 2018

E3S Web Conf.

Abstract. The effect of deflector curvature on hydrodynamic performances of a double-slotted cambered otter-board was investigated using engineering models in a wind tunnel. Four different curvature (0.06,0.09, 0.12 and 0.15) were evaluated at a wind speed of 28 m/s. Parameters measured included: drag coefficient Cx, lift coefficient Cy, pitch moment coefficient Cm, center of pressure coefficient Cp , over a range of angle of attack (0° to 70°). These coefficients were used in analyzing the differences in the performance among the four otter-board models. Results showed that the maximum lift coefficient Cy of the otter-board model with the curvature (0.06) of two deflectors was highest (2.020 at =55°). The maximum Cy/Cx of the otter-board with the curvature (0.12) of two deflectors was highest (3.655 at =22.5°). A comparative analysis of Cm and Cp showed that the stability of otter-board model with the curvature (0.12) of two deflectors is better in pitch, and the stability of otter-board model with the curvature (0.06) of two deflectors is better in roll. The findings of this study can offer useful reference data for the structural optimization of otter-boards for trawling.

Section: Introductionmentioning

confidence: 99%

Effect of deflector curvature on hydrodynamic performances of a double-slotted cambered otter-board

Shi

et al. 2018

E3S Web Conf.

“…Optimizing the structure of otter-boards may improve the hydrodynamic performance of the otterboard and reduce the energy consumption of fishing vessels [2][3]. Extensive studies on the hydrodynamic performance of otter-boards have been conducted in the United States, Japan, Norway, and other countries [4][5][6][7][8][9]. In China, researchers have studied the relevant hydrodynamic performance of otter-boards since the early 1980s, including the hydrodynamic performance and optimization of different otter-boards with various structure types.…”

Section: Introductionmentioning

confidence: 99%

Effect of deflector angle on hydrodynamic performances of a double-slotted cambered otter-board

Shi

et al. 2017

MATEC Web Conf.

Abstract. The effect of deflector angle on hydrodynamic performances of a double-slotted cambered otter-board is investigated using engineering models in a wind tunnel. Three different angle combinations (35°-30°, 30°-25°and 25°-20°) are evaluated at a wind speed of 28 m/s. Parameters measured included: drag coefficient Cx, lift coefficient Cy, pitch moment coefficient Cm, center of pressure coefficient Cp , over a range of angle of attack (0° to 70°). These coefficients are used in analyzing the differences in the performance among the three otter-board models. Results shows that the maximum lift coefficient Cy of the otter-board model with the angle combination (35°-30°) of two deflectors is the highest (2.160 at =55°). The maximum Cy/Cx of the otter-board with the angle combination (25°-20°) is the highest (3.842 at =2.5°). A comparative analysis of Cm and Cp shows that the stability of otter-board model with the angle combination (25°-20°) is better in pitch, and the stability of otter-board model with the angle combination (30°-25°) is better in roll. The findings of this study can offer useful reference data for the structural optimization of otter-boards for trawling.

“…By optimizing the structure of otter-board may improve hydrodynamic performance of the otter-board, and reducing the energy consumption of fishing vessels [2][3]. Currently, extensive studies on otter-board hydrodynamic performance had been conducted in the US, Japan, Norway and other countries [4][5][6][7][8][9]; In China, researchers have studied the relevant hydrodynamic performance of otterboard early since 1980s, and the series of optimization studies on otter-board structure is still necessary [10][11][12][13][14][15]. With the development of offshore fishing, higher requirements on the otter-board design is put forward, hydrodynamic performance improvement of otter-board will be the focus of future research.…”

Section: Introductionmentioning

confidence: 99%

Effect of bevel angle of three-layer parallel plate on hydrodynamic performances of otter-board

Zhou

et al. 2017

MATEC Web Conf.

Abstract. The effect of bevel angle of three-layer parallel plate of otter-board on hydrodynamic performances is investigated by model wind tunnel test. Four otter-board models are designed with four different bevel angles (8 °, 10 ° , 12° and 14 °) , and tested under the wind speed 28 m / s in wind tunnel. Model experiment is conducted to obtain the drag coefficients Cx, the lift coefficient Cy, the pitch moment coefficient Cm, the center of pressure coefficient Cp and calculated the lift-drag ratio Cy/Cx. The result shows that the maximum lift coefficient and the maximum lift-drag ratio of the otter-board model with a bevel angle 12 degree is higher, there is 2.598(=65°) and 2.607(=37.5°); For comparison in stability of otter-board, the stability of the otter-board model with the bevel angle 8 degree is better by the comparative analysis of Cm and Cp, the absolute value of Cm is 0.174 and the minimum variation coefficient of Cp is 4.37%. The results can offer reference for the structural optimization design of trawl otter-board.