基于流固耦合的硬涂层整体叶盘振动特性研究

Study on Vibration Characteristics of Hard Coating Blisk Based on Fluid Structure Coupling

整体叶盘在复杂多变载荷的作用下易出现振动损伤和使用寿命缩短等问题。针对此问题,以整体叶盘简化模型为对象,对叶片的压力面涂敷NiCrAlY硬涂层并建立叶盘的流场模型;在Fluent软件中采用流固耦合方法分别对无硬涂层、有硬涂层整体叶盘进行叶盘表面气动载荷的模拟;最后,采用预应力模态分析法对无硬涂层、有硬涂层整体叶盘在气动载荷、离心载荷、气动和离心载荷共同作用下的振动响应、等效应力的分布进行求解,以及绘制叶盘的坎贝尔图。依据以上求解结果,对比研究了硬涂层和3种载荷方式对整体叶盘振动特性的影响程度。结果表明:硬涂层对整体叶盘的振动特性影响较小;相比离心载荷,离心和气动载荷共同作用时对整体叶盘振动特性影响更明显;硬涂层会降低整体叶盘的共振点数。

Under the action of complex and variable loads,the blisk is prone to vibration damage and shortening its service life.To solve this problem,taking the simplified model of the blisk as the object,the pressure surface of the blade was coated with NiCrAlY hard coating,and the flow field model of the blisk was established;the fluid structure coupling method was used to simulate the aerodynamic load on the surface of the blisk without hard coating and with hard coating respectively by using Fluent software;finally,the prestressed modal analysis method was used to solve the vibration response and equivalent stress distribution without hard coating and with hard coating blisk under aerodynamic load,centrifugal load,aerodynamic and centrifugal load,and the Campbell diagram of blisk was drawn.Based on the above results,the effects of hard coating and three load modes on the vibration characteristics of blisk were compared.The results show that the hard coating has little effect on the vibration characteristics of the blisk;compared with centrifugal load,centrifugal and aerodynamic load have more significant influence on the vibration characteristics of blisk;hard coating can reduce the number of resonance points of the blisk.