基于γ-Re_(θt)转捩模型的二维翼型跨音速颤振边界预测  

Flutter boundary prediction of a two-dimensional airfoil in transonic flight regime with the γ-Re_(θt) transition model

作　　者：李国俊[1] 白俊强[1] 刘南[1] 徐家宽[1] 乔磊[1] 

机构地区：[1]西北工业大学航空学院,西安710072

出　　处：《振动与冲击》2017年第22期205-211,共7页Journal of Vibration and Shock

基　　金：国家"973"计划(2014CB744804)

摘　　要：转捩现象对跨音速流场和气动力有一定影响,但是目前大多数颤振问题研究主要采用全湍假设,并未对转捩现象加以考虑。基于非定常雷诺平均N-S方程(Reynold Averaged Navier-Stockes,RANS)和γ-Re_(θt)转捩模型,耦合结构运动方程,建立时域气动弹性分析方法,其中结构运动方程采用基于预估-校正技术的四阶隐式Adams线性多步法进行时域推进求解;分别对采用全湍假设和考虑转捩影响的Isogai案例A模型的跨音速颤振边界进行研究,从气动力做功的角度分析转捩对跨音速颤振特性的影响机制。结果表明转捩现象使得跨音速凹坑程度较全湍流动有所加深,凹坑范围扩大,跨音速凹坑最低点的颤振速度减小了41.6%;因此,在对表面存在转捩现象的翼型开展颤振分析时,必须在流场控制方程中添加转捩模型,从而准确分析颤振边界。Transition phenomenon has an impact on transonic flow field and aerodynamic force,but most of the current studies about flutter use fully turbulent hypothesis,which have no consideration about transition phenomenon.Therefore,the unsteady Reynold Averaged Navier-Stockes（ RANS） equation and γ-Re^-θttransition model,as well as structure dynamic equation were used to establish a time domain aeroelastic analysis method. The solution in time domain is fourth order implicit Adams linear multi-step method which is based on the prediction-correction method. The numerical simulations were used to analyze the transonic flutter boundary of Isogai Case A Model which was based on fully turbulent hypothesis and transition model respectively. These simulations were also made to analyze the influence mechanism of transition to flutter characters from the point of view about aerodynamic work. The results show that transition phenomenon makes the transonic dip deeper and wider than fully turbulent flow. Flutter speed in the deepest position of transonic dip has decreased by 41. 6%. Therefore,when flutter characters of wing which has transition on its surface is analyzed,the transition model must be added into fluid equations in order to analyze flutter boundary correctly.

关 键 词：转捩 时域 颤振 全湍 跨音速 

分 类 号：V215.34[航空宇航科学与技术—航空宇航推进理论与工程]