The influence rule of near-field wake vortex of tanker and the evaluation of dangerous area

加油机近场尾涡影响规律及危险区域评估

Key Laboratory of Aerodynamic Computational Simulation, Aeronautical Computing Technique Research Institute Aviation Industry Corporation of China, Xi'an 710019, China

Received: 22 June 2024

Abstract

The development of wake vortex of refuelling aircraft includes two stages: near-field and far-field. In the near-field stage, wake vortex is in the phase of rolling up and maturity. The evolution mechanism of wake vortex is complex and the resulting wake vortex is of great strength, which will adversely affect the safety and stability of downstream aircraft, especially small and medium-sized unmanned aircraft, so it is necessary to focus on the study of the development and influencing law of the wake vortex. The potential hazardous area is evaluated by analysing the tail vortex field. The Reynolds average method is used to simulate the near-field distribution of the wake vortex of the hypothetical tanker by using CRM aircraft, and the position of the vortex core and the influencing law and range of the wake vortex of the tanker under different incoming Mach numbers and crosswind conditions are analysed. On this basis, the configuration of the following UAV is selected as the research object of the receiver, and the coefficient of critical rolling moment is selected as the criterion of the dangerous area. The dangerous area of the wake vortex of the following aircraft behind the CRM refuelling machine is evaluated by using the calculation and analysis. The results show that increasing the Mach number makes the longitudinal position of the vortex core lower, the radius of the vortex core larger, and the circulation of the wake vortex at the same flow direction larger. The crosswind makes the vortex core position shift obviously. The larger the crosswind is, the larger the shift is, and the wake vortex dissipation will be accelerated at the same time. Under the influence of the wake vortex field of the refuelling aircraft, the potential dangerous area faced by the following UAV is mainly affected by the circulation of the wake vortex and the characteristic parameters of the following UAV, and the position of the dangerous area is consistent with the position of the vortex core.

摘要

加油机尾涡的发展包括近场和远场2个阶段, 近场阶段尾涡处于卷起和成熟期, 尾涡的演化机理复杂且形成的尾涡强度较大, 对下游飞机特别是中小型无人受油机的安全性和稳定性会造成不利影响, 因此需要重点研究近场尾涡的发展及影响规律, 通过分析尾涡流场对其潜在的危险区域进行评估。采用雷诺平均方法模拟以CRM飞机为假想加油机的尾涡的近场分布, 对不同来流马赫数和侧风条件下加油机近场尾涡的涡核位置和影响规律及范围进行分析, 在此基础上以"捕食者"无人机构型为受油机研究对象, 选取临界滚转力矩系数作为危险区域判据, 通过计算分析评估了受油机在CRM加油机后的尾涡危险区域。研究结果表明, 增大马赫数使得涡核在下落阶段纵向位置更低, 涡核半径变大, 尾涡环量变大; 侧风使涡核位置出现明显偏移, 侧风越大, 偏移量越大, 同时会加速尾涡耗散; 在加油机尾涡流场影响下, 受油机面临的潜在危险区域主要受加油机尾涡环量和受油机特征参数影响, 且危险区域位置与涡核位置变化保持一致。