一种单旋翼复合式直升机性能特性

为研究复合式直升机性能变化特性,构建了复合式直升机各气动部件数学模型组成的性能计算模型。以该计算模型为基础,通过不同的飞行条件约束,建立了复合式直升机的过渡飞行边界,研究了复合式直升机在边界内通过不同飞行路线从悬停模式到高速模式的飞行功率变化特点,分析了旋翼转速、前飞速度以及旋翼和机翼升力分配关系等参数对高速性能的影响。研究结果表明,复合式直升机从悬停模式过渡到高速模式通过旋翼卸载给机翼可降低飞行功率,且通过减小旋翼转速卸载比来减小旋翼总距卸载更为有效。但在过渡到高速模式时复合式直升机的旋翼转速也不能过低,过低的旋翼转速可能会增加飞行需用功率,同时也会对模型的配平产生影响,并且造成配平计算过程的迭代不收敛。

Performance characteristics of single rotor compound helicopter

In order to analysis the performance of the compound helicopter, a performance calculation model consisting of all the aerodynamics mathematical model parts is established. Based on the calculation model, using various flight conditions, we constructed the compound helicopter transition flight border, studied the characteristic variation of flight power from hover flight mode to high-speed flight mode by selecting different routes, and investigated the effects of multiple factors including rotor speed, forward speed, rotor and wing loading distribution in high-speed mode. The results indicated that the reduction of flight power could be achieved by increasing the offload lift from the rotor to the wing; moreover, it was more effective to reduce the rotor speed than reduce the rotor collective pitch, during the compound helicopter transits from hover mode to high-speed mode. The rotor could not operate at very low speed, which might increase the power consumption during high-speed flight mode. Furthermore, the low rotor speed could also influence the trim of the aircraft model, and made its calculation iteratively divergent.