氢动力固定翼无人机气动布局的气动特性评估

Aerodynamic Layout Evaluation of Hydrogen-powered Fixed-wing Unmanned Aerial Vehicle(UAV)by Numerical Simulation

以长航时氢能源混合动力固定翼无人机气动布局选型为研究需求,针对某设计方案开展了气动特性的数值模拟研究,以期为气动布局设计的评估和改型工作提供数据支撑。研究中分析了11个迎角(范围-6°~14°)状态下的气动力数据,比较了两种湍流模型下的计算结果,得到了该气动布局的升阻力特性曲线,并对SST k-ω模型下的速度场、流线、压力云图、压力曲线分布等流动细节进行了分析。结果显示:该无人机的气动性能较高,当迎角α=4°时能实现最大升阻比为14.5,失速迎角为8°,设计基本符合要求。同时,流场中涉及的速度、压力、流动分离等分布特征对进一步优化该款无人机的气动性能具有重要意义,为飞机气动布局方案的后续改进提供了依据。

For the aerodynamic layout selection of a long-endurance hydrogen energy hybrid unmanned aerial vehicle(UAV),this paper carried out a numerical simulation of aerodynamic characteristics for a certain design plan,in order to provide data support for the aerodynamic layout design evaluation and modification work.In the study,the aerodynamic data at 11 angles of attack(-6°~14°)were analyzed,the results of two turbulence calculation models were compared,and the respective lift-drag characteristic curves were obtained.In addition,the flow details such as velocity field,streamline,pressure cloud graph,and pressure curve distribution,were analyzed in detail.The results show that the UAV has a high aerodynamic performance,the maximum lift-to-drag ratio 14.5 can be obtained under the attack angle of 4°,and the stall angle of attack is 8°.The aerodynamic layout design basically meets the requirements.At the same time,the distribution characteristics of speed,pressure,and flow separation are of great significance for further understanding the aerodynamic performance of the UAV.The assessment results provide a basis for the subsequent improvement of the aerodynamic layout plan.