火星直升机配平和稳定性研究

Study on the trim and stability of Mars helicopter

由于火星环境的特殊性,在地球上几乎不可能完全复制火星环境进行试验,因此火星直升机设计过程更加依赖分析、建模和仿真。首先分析了火星环境,以NASA设计的火星直升机为算例,建立了火星直升机飞行动力学模型。建模过程中,重点讨论了火星环境下的翼型气动力计算、旋翼挥舞运动方程和旋翼入流模型,并考虑了上下旋翼间的气动干扰,同时采用CFD方法计算了机身的气动力。然后,依据所建立的飞行动力学模型,对样例火星直升机进行了配平和稳定性计算,并对计算结果进行了分析。计算和分析结果表明,火星直升机纵、横向稳定性较差,这一特性很大程度上限制了火星直升机的最大飞行速度,导致直升机飞行性能劣化。

Because of the special environment on Mars, it was almost impossible to replicate the Mars environment completely on the Earth. Therefore, the design process of Mars helicopter was more dependent on analysis, modeling and simulation. Firstly, the Mars environment was analyzed, and the flight dynamics model of the Mars helicopter designed by NASA was established. In the process of modeling, the equations of rotor flap motion and rotor inflow model were discussed, and the aerodynamic interference between the upper and lower rotors was considered. At the same time, the aerodynamic force of the fuselage was calculated by CFD method. Based on the established flight dynamics model, the trim and stability of the sample Mars helicopter were calculated, and the calculation results were analyzed. The results show that the Mars helicopter has poor longitudinal and lateral stability, which greatly limits the maximum flight speed of the Mars helicopter, leading to the deterioration of its flight performance.