帆板迎风摇帆频率和幅度的动力学分析与设计

Dynamic Analysis and Design of Pumping Frequency and Amplitude for RS:X Class on theWindward Leg

目的:探明迎风阶段摇帆频率和幅度组合方案对帆翼推进性能的影响,为运动员在迎风起航、紧急避让及迎风航行等过程提供个性和科学的摇帆调控建议,助力运动员对帆翼的科学操控。方法:确定运动员摇帆特征并建立帆翼运动模型,采用URANS方法,调用SST k-ω湍流模型,求解迎风摇帆时帆翼空气流场气动力变化规律。基于力学分析建立帆翼推进性能评价方法,并研究攻角20°的帆翼在风速3 m/s迎风、频率0.67~2.00 Hz和幅度2°~10°组合工况下的帆翼推力系数和能耗系数。结果:摇帆频率为0.67~1.00 Hz时,推力系数和偏航力系数平均值随幅度增加而增大;摇帆频率为1.30~2.00 Hz时,推力系数和偏航力系数平均值均随幅度增加呈现先增大后减小的趋势,配合幅度8°摇帆可使推进性能最优;摇帆能耗系数随幅度和频率增加而增大,高频大幅摇帆能耗是低频大幅的25倍,是高频小幅的10倍。结论:为促进运动员帆翼推进性能的最优,低频摇帆应配合较大的幅度,而高频摇帆则需配合适宜幅度。

Objective:To explore the impact of the combination of frequency and amplitude on the pumping propulsion performance of the sail wing,so as to provide personalized and scientific suggestions for athletes to control sailing.Methods:Determining the sailing characteristics and establishing the pumping model firstly,then the SST k-ωturbulence model was employed to solve the aerodynamic variation of the pumping wing based on URANS.Under the condition of 20°attack angle and 3 m/s speed of upwind,the thrust coefficient and energy consumption coefficient of the sail wing with a combination of 0.67-2.00 frequencies and 2-10°amplitudes were investigated.Results:When the pumping frequency was 0.67 Hz to 1.00 Hz,the thrust coefficient and yaw force coefficient were increased with amplitude.When the pumping frequency was 1.30 Hz to 2.00 Hz,both thrust coefficient and yaw force coefficient were increased firstly and then decreased,and the wing propulsion performance was optimal when amplitude was 8°.The energy consumption coefficient of the pumping wing was elevated with amplitude and frequency,the energy consumption of large-amplitude plus high-frequency was 25 times higher than that of large-amplitude plus low-frequency,and 10 times higher than that of small-amplitude plus high-frequency.Conclusion:To achieve the optimal propulsion performance,the low frequency pumping should combine with a larger amplitude,while the high frequency pumping should combine with a middle amplitude.