侧风条件下短舱进气道地面涡数值模拟

为了研究起飞状态下进气道地面涡的形成与发展规律,针对缩比的短舱进气道模型进行了3维数值仿真,分析了来流速度和短舱进气道距地面高度对地面涡的影响,得到了地面涡的特点以及对进气道流场品质的影响。研究结果表明:侧风来流速度越低,越容易形成地面涡,随着侧风来流速度的增高,地面涡会消失;短舱进气道距地面高度越低,越容易形成地面涡,地面涡的环量越大;地面涡的形成会增大进气道出口截面的流场畸变程度,短舱进气道距地面高度对畸变的影响很小,畸变主要受侧风来流速度的影响。最后给出了侧风条件下地面涡的分界线方程,可作为是否存在地面涡的判断依据。

Numerical Simulations on Nacelle Inlet Ground Vortex under Crosswind Conditions

In order to investigate the formation and development of the ground vortex under take-off conditions, 3D numerical simulation on scaled nacelle inlet models were conducted. The influence of far-field velocity and the height between nacelle inlet and ground on the ground vortex was analyzed. The characteristics of the ground vortex and the influence of the ground vortex on quality of flow field were obtained. The results show that the lower the crosswind velocity is, the easier the ground vortex forms. When the crosswind velocity increases to a certain value, the ground vortex will disappear. The lower the height between the nacelle inlet and the ground is, the easier the ground vortex forms and the greater the ground vortex circulation becomes. When the ground vortex is formed, the distortion of the inlet is increased. The flow field distortion is mainly influenced by crosswind velocity and the height between the nacelle inlet and ground has little influence on the distortion. The boundary line equation of the ground vortex under crosswind conditions is established and it can be basis for judgment whether there are ground vortices.