新一代战斗机非定常流动数值研究综述

新一代战斗机强调超机动能力和强隐身性,其中大攻角下的静态失速、动态失速及内埋弹仓绕流是与高机动和强隐身密切相关的、极具挑战的几类典型的非定常流动,它们对数值方法提出了极高的要求。为了高精度地仿真流场、清楚地揭示流动机理,有效地控制非定常流动,非常有必要发展高精度且高效率的RANS-LES混合方法体系,包含RANS-LES混合方法本身、与RANS-LES混合方法匹配的高精度自适应耗散格式、基准湍流模式、高质量计算网格、高精度时间推进方法、非定常量的统计方法等,具有极强的紧迫性。提出、发展、验证并应用该类方法数值仿真新一代战斗机（包括单独部件、组合体、甚至全机）的非定常流动,数值预测结果与风洞实验数据吻合良好;此类方法可为新型战斗机设计提供理论依据和分析手段。

Review of numerical research on unsteady flows of the new generation fighters

The new generation fighters emphasize the super-maneuverability and high stealthy properties. The static stall and dynamic stall at high angles of attack and unsteady air-loads around the embedded weapon bay at supersonic speed are very challenging. The high accuracy and efficiency numerical simulations are urgently required. To simulate the flowfields accurately, clearly explore the flow mechanisms and effectively control the unsteady airloads, it’s required to develop the highly accurate and efficient Reynolds-Averaged Navier-Stokes and Large Eddy Simulation (RANS-LES) hybrid model, including the model itself, the coupled high-order adaptive dissipation scheme, fundamental turbulence model, high quality computational grids, high-order time marching method, the statistical method of unsteady flow, and so on. This kind of RANS-LES hybrid model has been proposed, developed, validated and applied to the new-generation fighters, including the single component, junctions, even complete fighters. After comparing with the measurements, the numerical simulations perform very well, including the mean forces, and the pressure fluctuations. Therefore, the RANS-LES hybrid model can provide the theoretical basis and analyzing tools for the new-generation fighter design.