基于等效单自由度的涡轮扫频振动研究  

A Vibration Frequency Sweeping Algorithm Based on Equivalent Single Degree of Freedom for Turbine

作　　者：张虹[1] 张一帆 王新宇 董洪祯 ZHANG Hong;ZHANG Yifan;WANG Xinyu;DONG Hongzhen(School of Mechanical Engineering,Beijing Insutitute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学机械与车辆学院,北京100081

出　　处：《北京理工大学学报》2024年第3期270-277,共8页Transactions of Beijing Institute of Technology

基　　金：国家自然科学基金资助项目(52376167)。

摘　　要：针对有限元方法对扫频工况下涡轮振动求解出现的困难,提出了基于等效单自由度的涡轮结构振动扫频算法,并对涡轮扫频振动特征进行分析.建立了涡轮流固耦合计算模型,使用非线性谐波法得到了涡轮表面的气动激励,使用谐响应方法分析了涡轮的稳态振动特性.基于能量原理,建立了涡轮等效单自由度计算模型,通过与稳态振动结果的对比,验证了方法的可行性与正确性,并利用所建立模型分析了涡轮的扫频振动特征.结果表明,涡轮在扫频工况下响应峰值、半功率带宽以及响应曲线形状等特征与稳态工况存在差异.等效单自由度算法与有限元方法计算得到的涡轮响应误差小于10%,共振峰偏移率小于1%.To solve the difficulties in obtaining turbine vibration under sweep-frequency conditions with the finite element method,a structural vibration frequency sweeping algorithm based on an equivalent single degree of freedom(SDOF)was proposed to analyze the characteristics of turbine vibration.Firstly,a fluid-structure coupling computational model of the turbine was established,obtaining the turbine surface's aerodynamic excitation with a non-linear harmonic method,and analyzing the steady-state vibration characteristics of the turbine surface with the harmonic response method.Then,an equivalent SDOF computational model was developed based on the energy principle for turbine.And comparing the computational model with the steady-state calculation method,its feasible and accurate was validated.Finally,the SDOF computational model was used to analyze the sweep vibration characteristics of turbine.The results show that,there are differences in the peak response,half power bandwidth,and response curve shape of the turbine between the conditions under sweep frequency and steady-state.The turbine response error calculated by the equivalent single degree of freedom algorithm and finite element method is less than 10%,and the formant offset is less than 1%.

关 键 词：涡轮 流固耦合 扫频振动 单自由度 谐响应 

分 类 号：TK412.4[动力工程及工程热物理—动力机械及工程]