基于CFD/CSD紧耦合的旋翼翼型气弹分析

Aeroelastic analysis of rotor airfoil based on CFD/CSD tight coupling method

采用CFD/CSD(计算流体力学/计算结构力学)紧耦合的方法,以Fluent软件作为主控平台,通过UDF(用户自定义函数)及I/O(输入/输出)文件读写的方式实现结构响应和气动载荷的数据交换,耦合求解了旋翼桨叶剖面的气动力和振动响应.在此基础上研究旋翼桨叶剖面在变距、沉降(挥舞)和周期交变来流条件下的气动特性和振动响应特性.结果表明:桨叶剖面在轻失速情况下,气动载荷周期性比较好,表现出光滑的迟滞环曲线,结构沉降响应也表现出光滑的周期性现象,扭转响应出现局部轻微振荡.深失速情况下,气动载荷及结构响应都表现出强烈的非线性振荡,高频成分较为明显.

By coupling the calculation of the unsteady aeroforce and the vibration response through the development of CFD/CSD （computational fluid dynamics/computational structure dynamics） tight coupling method, the Fluent code was calculated, and the data of structural response and dynamic load were exchanged by UDF （user defined function） and reading and writ- ing the I/O （input/output） files. The aerodynamic characteristics and vibration response of the airfoil at the condition of pitching motion, plunging （flapping） motion and periodic alternating incoming flow were studied. Numerical results indicated that the aerodynamic load was periodic, showing a smoothing hysteresis curve in rotating process, and the flapping responses also showed a cyclical phenomenon, the pitching response showed slight oscillation at slight stall con- dition. At the deep stall condition, the aerodynamic load or structural response showed strong nonlinear oscillation, high frequency components were more obvious.