共轴刚性旋翼气动干扰特性风洞试验研究

针对共轴刚性旋翼上下旋翼间复杂气动干扰问题,利用4 m直径共轴刚性旋翼缩比模型开展了悬停及前飞状态风洞试验研究。试验中,采用两套六分量天平对共轴刚性旋翼的上下旋翼进行分开测力,并测量了相同操纵量输入时的孤立单旋翼气动力。通过分析双旋翼状态下的上下旋翼与孤立单旋翼的气动力的对比结果,研究了共轴刚性旋翼在悬停及前飞状态下的气动干扰特性。在此基础上,还进行了升力偏置对气动干扰影响的试验研究。结果表明:随着旋翼前进比的增大,上下旋翼之间的气动干扰逐渐减弱,共轴刚性旋翼的非对称气动干扰会使得双旋翼升力偏置增大。

Wind Tunnel Test Investigation of Coaxial Rigid Rotor Aerodynamic Interaction

The wind tunnel of a 4 m-diameter coaxial rigid model rotor is conducted to investigate the aero-dynamic interaction characteristics. Both coaxial and single rotor are tested, and the upper and lower rotor forces are measured independently. The force distribution of the coaxial rotor is analyzed. The aerodynamic forces and lift offset characteristics of coaxial and single rotor are compared. Simultaneity, the free wake method is used to analyze the tip vortex wake characteristic under interference. It is shown that the coaxial rigid rotor interaction is weaken as advance ratio increases, and the coaxial rigid rotor lift offset increases due to the asymmetry aerodynamic interaction.