飞机燃油质量特性计算的截面自适应分割法

针对飞机燃油系统方案设计阶段截面连续变化的飞机油箱，提出了具有截面自适应性的燃油质量特性计算方法。首先根据飞行姿态和过载计算油面法向量，确定最低油面位置；然后根据等效燃油实体确定分割步长进行首次分割，并根据截面面积的变化情况，通过后续分割对误差进行补偿，直至分割精度达到预设精度阈值要求；最后对分割后的燃油实体进行燃油质量特性测量和计算。针对某型无人机燃油系统中多种不同类型的截面连续变化油箱进行仿真验证，表明该方法具有截面自适应性，且相比共轭梯度寻优算法，能够在保证计算精度的情况下，计算效率提升71.43%~92.31%，适用于飞机燃油系统方案设计阶段通过燃油质量特性计算快速准确地判断设计方案在重心方面的可行性。 

Adaptive cross-section segmentation method for aircraft fuel mass properties calculation

For aircraft fuel tanks with continuously varying cross section in aircraft fuel system design, a method for calculating fuel mass properties with cross-section adaptability is proposed. Firstly, the fuel level normal vector is calculated using flight attitude and overload to determine the location of the lowest fuel level. Secondly, the split step is determined based on equivalent fuel entity to perform the first segmentation, and errors will be compensated through subsequent segmentations according to the cross-sectional area changes until the segmentation accuracy reaches preset accuracy threshold. Finally, fuel mass properties are measured and calculated for the segmented fuel entities. The simulation carried out for different types of fuel tanks with continuously varying cross section in fuel system of a certain type of UAVs shows that this method has the cross-section adaptability and can improve calculation efficiency by 71.43%-92.31% compared with conjugate gradient optimization algorithm, while ensuring calculation accuracy. It is suitable for quick and accurate determination of feasibility of design schemes in terms of gravity center by calculating fuel mass properties.