In this paper, a concept of multi rotor micro air vehicle ( MAV), which can motion to any direction even rolling on the ground, was presented. Three configurations of this vehicle were analyzed and the equations of motion were built. The vehicle has smaller sizes of shape, lighter weight and lower flight speed. As a result, Reynolds number of airfoil for this vehicle, based on rotor velocity, rotor chord length and flight mode of the vehicle, was varied from 1×104 to 12.8×104. A fairly conventional low Reynolds number airfoil section (Eppler 387 ) was chosen for the analysis. Aerodynamic characteristics of airfoil at low Reynolds number were investigated in order to better understand the behavior of airfoils in different flight regime using conformal hybrid meshes. The lift coefficient, drag coefficient and ratio of lift coefficient to drag coefficient at Reynolds number of 1×104, 2×104, 3×l04 and 6×104, respectively, for a series of attack angle, were obtained, no study at Reynolds number less than 6×104 before. The results of simulation were compared to the results of experiment and the agreement of trend of both is very well.%提出了一种新结构的六转子无人飞行器的概念,该飞行器可以在空间任意方向飞行,甚至可以在地面上滚动前进.分析了其可能的三种构型并给出了各自的运动方程,给出了三轴解耦时该飞行器的配置方式及转子空间位置.由于该飞行器具有小尺寸外形、低重量和飞行速度慢的特点,根据转子速度、弦长和飞行模态,计算得该飞行器的雷诺数变化范围为1×104到12.8×104.以选用的Eppler 387翼型作为分析对象,采用正投影混合网格方法对其在低雷诺数下的气动性能进行研究,得到了雷诺数分别为1×104,2×104,3×104和6×104下对应不同迎角的升力系数、阻力系数和升阻比,并对雷诺数为6×104下的升力系数仿真结果同试验结果进行了对比,二者具有较好的一致性.制作了六转子微型飞行器样机,实现了垂直起降及慢速前飞.
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