共轴倾转旋翼性能计算方法

共轴倾转旋翼飞行器是一款可折叠机翼的高速旋翼飞行器。本文建立了适用于共轴倾转旋翼飞行器直升机模式、倾转过渡模式和固定翼飞机模式的旋翼性能计算方法,并对比风洞试验数据验证了共轴倾转旋翼轴流状态的性能和共轴双旋翼前飞状态的性能。在此基础上,分析了共轴倾转旋翼在倾转过渡状态各性能参数的变化规律、上下旋翼诱导速度的分布情况、上下旋翼之间的干扰面积和干扰因子的变化趋势。结论表明:相同来流速度下,当倾转角增大,共轴倾转旋翼的拉力系数减小,功率系数先增大后减小,上下旋翼的受干扰面积和干扰因子均增大。

Mathematical Model for Performance of Coaxial Tilt-Rotor

The coaxial tilt-rotor craft is a high-speed rotorcraft along with deployable fixed-wings. A mathematical model is built for analyzing the performance of coaxial tilt-rotor in helicopter flight condition, transition condition and fixed-wings airplane flight condition. Firstly, the application of the model shows good agreement with the experiment from wind tunnel test of coaxial tilt-rotor in axial state and coaxial rotor in forward flight. Then, the method is studied by analyzing the obtained results of the variation of performance parameters, the distribution of induced velocity, the change of overlap area and interaction factor in transition condition. The calculated results show that when the tilt angle increases at constant flow, the thrust coefficient of coaxial tilt-rotor decreases, the power coefficient increases first and then decreases, the overlap area and the interaction factor of upper and lower rotors both increase.