共轴刚性旋翼悬停状态桨叶表面压力测量试验与计算研究

针对共轴刚性模型旋翼悬停状态，开展了桨叶表面压力测量试验与数值模拟研究。试验采用微型压力传感器进行桨叶表面压力测量，不仅获得了桨叶表面压力的试验数据，同时为CFD计算方法计算桨叶表面压力提供了验证数据。计算与试验结果对比吻合度良好，验证了CFD计算方法的有效性。研究获得了共轴刚性旋翼上下旋翼桨叶表面的流动情况和压力特性，结果表明:对于上下各4片桨叶的共轴刚性旋翼，桨叶表面压力随着桨叶旋转呈周期性变化，旋转一周出现8个小周期；在上下旋翼扭矩配平的悬停状态，下旋翼桨叶大部分区域受下洗流影响，下旋翼剖面拉力低于上旋翼；在桨尖区域，下旋翼的桨距角大于上旋翼，受各自上洗流的影响，下旋翼剖面拉力高于上旋翼。 

Experimental and computational study on blade surface pressure measurement of coaxial rigid rotor in hovering state

For the coaxial rigid model rotor in hovering state, the experimental and numerical simulation research on blade surface pressure measurement were carried out. The micro pressure sensor was used to measure the blade surface pressure, which not only obtains the experimental data of blade surface pressure, but also provides verification data for CFD method to calculate the blade surface pressure. The calculation results are in good agreement with the experimental results, which verifies the effectiveness of CFD method. The flow and pressure characteristics of the upper and lower rotor blade surface of the coaxial rigid rotor were obtained. The results show that, for coaxial rigid rotor with 4 upper blades and 4 lower blades, the blade surface pressure changes periodically with the rotation of the blade, and there are eight small cycles in one rotation cycle. In the hovering state of the upper and lower torque balancing, most of the area of the lower rotor blade is affected by the downwash flow, and the profile pull of the lower rotor is lower than that of the upper rotor; total pitch angle of the lower rotor in the tip region is larger than that of the upper rotor, and affected by respective upwash flow, the profile pull of the lower rotor is higher than that of the upper rotor.