Low Dissipation Simulation for Vortex Flowfield of Rotor in Hover Based upon Discontinuous Galerkin Method  

基于间断伽辽金法的悬停状态旋翼涡流场低耗散数值模拟

作　　者：BIAN Wei ZHAO Qijun ZHAO Guoqing 卞威;招启军;赵国庆(南京航空航天大学航空学院直升机旋翼动力学国家级重点实验室,南京210016;中国空气动力研究与发展中心旋翼空气动力学重点实验室,绵阳621000)

机构地区：[1]National Key Laboratory of Rotorcraft Aeromechanics,College of Aerospace Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,P.R.China [2]Rotor Aerodynamic Key Laboratory,China Aerodynamic Research and Development Center,Mianyang 621000,P.R.China

出　　处：《Transactions of Nanjing University of Aeronautics and Astronautics》2021年第6期975-983,共9页南京航空航天大学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.12072156, 12032012);the Foundation of Rotor Aerodynamic Key Laboratory (No.RAL20190102);the Priority Academic Program Development Project of Jiangsu Higher Education Institutions(PAPD)。

摘　　要：The discontinuous Galerkin(DG) method is established and innovatively conducted on accurately simulating the evolution of blade-tip vortex and the aerodynamic characteristics of helicopter rotor. Firstly,the Reynolds-Averaged Navier-Stokes(RANS)equations in rotating reference frame are employed,and the embedded grid system is developed with the finite volume method(FVM)and the DG method conducted on the blade grid and background grid respectively. Besides,the Harten-Lax-Van Leer contact(HLLC)scheme with high-resolution and low-dissipation is employed for spatial discretization,and the explicit third-order Runge-Kutta scheme is used to accomplish the temporal discretization. Secondly,the aerodynamic characteristics and the evolution of blade-tip vortex for Caradonna-Tung rotor are simulated by the established CFD method,and the numerical results are in good agreement with experimental data,which well validates the accuracy of the DG method and shows the advantages of DG method on capturing the detailed blade-tip vortex compared with the FVM method. Finally,the evolution of tip vortex at different blade tip Mach numbers and collective pitches is discussed.建立间断伽辽金方法并将其应用于直升机旋翼桨尖涡演化和气动特性的精确模拟。首先,选取旋转参考坐标系下的雷诺平均N-S方程作为控制方程,采用嵌套网格方法对旋翼流场进行模拟,在桨叶网格和背景网格上分别采用有限体积法和间断伽辽金法。此外,空间离散采用高分辨率、低耗散的Harten-Lax-Van Leer contact(HLLC)格式,时间离散采用显式三阶龙格-库塔格式。然后,采用所建立的CFD方法对C-T旋翼的气动特性和桨尖涡演化进行了数值模拟,计算结果与试验数据吻合较好,很好地验证了间断伽辽金方法的准确性,展示了其相较于有限体积方法在捕捉桨尖涡细节方面的优势。最后,对比分析了在不同桨尖马赫数和旋翼总距下旋翼桨尖涡的演化规律。

关 键 词：blade-tip vortex discontinuous Galerkin(DG)method Navier-Stokes(N-S)equations aerodynamic characteristics helicopter rotor 

分 类 号：V211.52[航空宇航科学与技术—航空宇航推进理论与工程]