菱形连翼布局俯仰力矩非线性特性数值分析

采用数值模拟和理论分析相结合的方法,对高空长航时(HALE)菱形连翼布局无人机(UAV)的俯仰力矩非线性特性进行了研究。研究结果显示菱形连翼布局飞机具有2个明显的俯仰力矩非线性区域并存在上仰现象。通过采用湍动能来表示后翼受前翼尾流直接扫掠而导致的流场结构改变的强度和影响范围来解释其中一个俯仰力矩非线性区域出现的原因。通过分析前后翼流场分离的特性来解释出现另一个俯仰力矩非线性区域和力矩上仰的原因。研究了总体布局参数变化对菱形连翼布局无人机俯仰力矩特性的影响,结果显示通过调整总体布局参数可以有效地缓解俯仰力矩特性曲线非线性对飞行性能带来的影响。

Numerical analysis of pitching moment non-linear characteristics of diamond joined-wing configuration

Investigation on the pitching moment non-linear characteristics of the high-attitude long-endurance (HALE) diamond joined-wing configuration unmanned aerial vehicle (UAV) was carried out by both numerical simulation and theoretical analysis method.The results show that the aircraft have two obvious pitching moment non-linear regions and there is a pitch-up phenomenon.The turbulent kinetic energy is used to represent the strength and the influence area of flow field structure of the aft-wing changed by the frt-wing wake direct sweep,which explains one of the causes of the non-linear region of the pitch moment.The other reason for the pitching moment non-linear region and pitch-up moment is explained by analyzing the separation characteristics of the aft-wing and the frt-wing.The influence of the general layout parameters of the UAV on the pitching moment characteristics of diamond joined-wing UAV was studied.The results show that adjusting the overall layout parameters can effectively mitigate the impact of pitching moment non-linear characteristics on flight performance.