通航飞机改货运无人机气动修形讨论

Comments on aerodynamic modification design of cargo UAV based on general aviation airplane

对已有的通航飞机进行改造是无人机研制的一种途径,气动修形相对新布局设计具有周期短、成本低的特点,是一种可行的工程设计方法。使用基于N-S方程的数值模拟方法分析了某通航飞机的气动特性,指出影响其阻力特性的外形特征点。在保证机体容积不减小的条件下,对机头和机身后端进行了气动修形设计。计算结果表明,典型位置处的绕流流场特性有较为明显的改善,全机表面积减小了2.2%,机身阻力系数减小了21.3%,全机最大升阻比增大了14.9%。

It is a practical option to develop UAV by modifying the existed general aviation airplane. The aerodynamic modification design could be an efficient engineering method for its short development cycle and low cost. The aerodynamic characteristic of a general aviation airplane was discussed by numerical simulations based on N-S equations, showing typical geometry features related with drag. Aerodynamic modification design was carried out for the nose and tail areas of the initial airplane without any reduction of the fuselage volume. It is shown that the wetted area decreases by 2.2%, and the drag of fuselage decreases by 21.3%, leading to 14.9% increasement of lift-to-drag for the airplane.