【摘要】 发展适合于叶轮机械风扇叶片反扭设计的流固耦合计算方法,综合考虑气动力和离心力对叶片变形的影响;以设计叶型为目标,预测冷态加工叶型并进行叶片的变形分析,比较变形后叶型和设计叶片的偏差并修正冷态叶型直到迭代收敛。在叶片变形分析中考虑了气动力随叶型变化的非线性作用,在每一时间步同步求解流体运动方程和叶片变形的控制方程并交换边界信息;流体域求解了时间精确的非定常雷诺平均Navier-Stokes方程,以得到每一步由于叶片变形而引起的流场变化;叶片变形则由积分叶片表面受到的气动力并求解结构动动力学方程得到;流体域和固体域的信息交换采用了一种使用投影-形函数插值的新方法。采用该方法对NASAROTOR67风扇叶片进行反扭设计,得到冷态制造叶型和叶片扭转角随叶高的变化规律。更多还原

【Abstract】 A novel iterative method is presented for turbomachinery blade un-running design with a fluid-structure coupled method.The effect of aerodynamic and centrifugal loads on blade deflections is considered in the process.Starting with a blade definition designed by an aerodynamic method,the procedure predicts a manufacturing blade profile,and computes blade deflections due to aerodynamic and centrifugal loads.The manufacturing blade profile is corrected accounting for the difference between the target blade shape and the newly deformed shape.The calculation of blade deflection due to aerodynamic loads simulates the interaction of fluid/structure at each time step,thus it is capable of accounting for the nonlinear aerodynamic contributions due to the blade deforming.In the aerodynamic domain,time accurate unsteady Reynolds averaged Navier-Stokes equation is solved in order to simulate the effect of blade deflections on the flow fields.The blade deflection is computed by solving structure dynamic equations with aerodynamic forces as boundary conditions.The information exchanges at each time step by an innovative projection-interpolation procedure with shape functions in order to transfer information between non-matching surface grids in the aerodynamic and structure domains.The method is used to predict the manufactured blade profile of NASA rotor 67 transonic fans,the predicted blade profile and the twist angle of the blade at various spans is presented.The results show that the proposed method for blade un-running design predicted more accurate manufactured fan blade shapes.更多还原