某新型无人帆船的结构设计及翼帆气动性能分析

Structural Design of a New Type of Unmanned Sailboat and Analysis of the Aerodynamic Performance of the Wing Sail

为了满足无人帆船在进行海洋调查时航时长、范围大和寿命高的要求,本文设计了一款新型无人帆船。通过SolidWorks软件建立无人帆船的三维模型,并采用计算流体动力学(computational fluid dynamics,CFD)对翼帆的气动性能进行分析。在考虑帆船航行实际工作状态的前提下,通过比较柔性帆、刚性帆和翼型对称截面与非对称截面的性能,确定了主帆为NACA 0021,尾翼为NACA 0018翼型的对称刚性帆,以提高帆船的气动性能。同时,采用与飞机升降舵类似结构的尾翼控制翼帆与来流的攻角,极大地降低了控帆的难度与功耗。为分析翼帆的气动性能,选用SST k-ω模型在Fluent中进行模拟分析。研究结果表明,翼帆的升力系数较大,空气流动平稳,并未出现涡流区,同时,翼帆表面压力呈现平滑的过渡现象,使气流可以平稳的从主帆表面分离,满足设计要求。该研究对使用无人帆船探索海洋具有重要意义。

In order to meet the requirements of long sailing time,large range and long lifespan for unmanned sailing ships in ocean surveys,this paper designs a new type of unmanned sailing ships.The 3D model of the unmanned sailboat is established by SolidWorks software,and the aerodynamic performance of the wing sail is analyzed by computational fluid dynamics.Under the premise of considering the actual working conditions of sailing,by comparing the performance of flexible sails and rigid sails and airfoil symmetrical and asymmetrical cross-sections,it is determined that the main sail is NACA 0021 and the tail is a symmetrical rigid sail with NACA 0018 airfoil,so as to improve the aerodynamic performance of sailboats.At the same time,the use of a tail wing structure similar to that of an airplane elevator controls the angle of attack of the wing sail and the incoming flow,which greatly reduces the difficulty and power consumption of sail control.In order to analyze the aerodynamic performance of the wing sail,the SST k-ω model is selected for simulation analysis in Fluent.The research results show that the lift coefficient of the wing sail is large,the air flow is stable,and there is no vortex area.At the same time,the surface pressure of the wing sail presents a smooth transition phenomenon,which makes the air flow can be separated from the surface of the main sail smoothly to meet the design requirements.This research is of great significance to the use of unmanned sailboats to explore the ocean.