基于CFD/CSD耦合方法的旋翼降转速气动特性  

Slowed rotor aerodynamic characteristics using CFD/CSD coupling method

作　　者：张凯[1] 招启军[1] 马砾 徐国华[1] ZHANG Kai;ZHAO Qijun;MA Li;XU Guohua(National Key Laboratory of Helicopter Aeromechanics,College of Aerospace Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]南京航空航天大学航空学院直升机动力学全国重点实验室,南京210016

出　　处：《航空动力学报》2024年第12期38-52,共15页Journal of Aerospace Power

基　　金：江苏高校优势学科建设工程资助项目;国家重点实验室基金(61422202201);国家自然科学基金(12102186)。

摘　　要：为研究UH-60A直升机旋翼降转速大前进比状态气动特性及反流区流动机理,采用考虑桨叶弹性变形的高精度CFD/CSD耦合方法进行数值模拟分析。CFD模块采用运动嵌套网格方法,主控方程为耦合Spalart-Allmaras(S-A)湍流模型的Navier-Stokes(N-S)方程,时间离散采用隐式lower-upper symmetric Gauss-Seidel(LU-SGS)双时间推进法;CSD模块采用中等变形梁假设,通过Newmark-Beta方法求解桨叶运动微分方程。通过UH-60A前飞状态计算值与飞行测试数据的对比验证CFD/CSD耦合方法的有效性,在此基础上,开展了UH-60A旋翼在40%工作转速不同前进比及相同前进比不同转速下气动特性研究。计算结果表明:在大前进比状态下总距对旋翼气动特性影响减弱,气动性能有所降低,大前进比产生的大反流区内存在自身桨-涡干扰、深度失速等复杂流动现象,高精度CFD/CSD耦合方法对该现象进行了有效模拟。To study the aerodynamic characteristics and the flow mechanism of reverse flow region of a slowed UH-60A rotor at high advance ratios,accurate numerical simulation analysis was carried out by the CFD/CSD coupling method considering the elastic deformation of rotor blade.The CFD module adopted a moving-embedded grid system with Navier-Stokes(N-S)equations as the governing equations,and Spalart-Allmaras(S-A)turbulence model was employed.An implicit lower-upper symmetric Gauss-Seidel(LU-SGS)dual-time algorithm was adopted for temporal discretization.As for the CSD module,the finite element method of moderate deflection beam model was employed.The blade differential equations of motion were formulated and calculated using Newmark-Beta method.The CFD/CSD coupling method validity was verified by comparing the aerodynamic loads of UH-60A with the flight test data.Then,the aerodynamic characteristics of the UH-60A rotor slowing down to 40%at different advance ratios and same advance ratio with different rotation rates were studied.The results showed that the influence of collective pitch on the aerodynamic characteristics was weakened and the aerodynamic performance was reduced at high advance ratio.Large advance ratio produced large inverse flow region,where complex flow phenomena such as blade-on-blade interactions and deep dynamic stall occurred.And the high accuracy CFD/CSD coupling method can effectively simulate these phenomena.

关 键 词：旋翼 CFD/CSD耦合方法 低转速 大前进比 UH-60A 

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]