火箭推进2025，Vol.51Issue(2)：125-131,7.DOI:10.3969/j.issn.1672-9374.2025.02.013
整体式涡轮盘结构阻尼比精确测量方法
Precise measurement method for structural damping ratio of integral turbine disks
摘要
Abstract
The dynamic structural characteristics serve as the foundation for analyzing flutter and forced response issues of integral turbine disks.Although the structural damping of the integral turbine disk is relatively small when the aerodynamic damping is negative,it remains the sole source of energy dissipation.To achieve precise measurements of damping ratios of the turbine disk at various orders,the free decay curves of the turbine disk under hammer impact was collected,and the time-domain curves using fast fourier transform(FFT)was analyzed to identify the peak frequencies and determine the frequency bands of interest.The chirp Z-transform(CZT)method was employed to perform the spectrum of specific frequency bands,and the frequencies corresponding to a 3 dB decrease in amplitude by interpolation was determined.Finally,using the half-power bandwidth method,the first five orders of damping ratios of the turbine disk was calculated,which were 6.6×10-4,4.8×10-4,1.3×10-3,4.5×10-4 and 6.5×10-4,respectively.The study results show that the CZT-based half-power bandwidth method overcomes the insufficient frequency resolution problem of the traditional FFT method in turbine disk damping identification,enabling the precise measurement of structural damping ratios as low as 10-4.关键词
涡轮盘/结构阻尼比/颤振/半功率带宽法Key words
integral turbine disk/structural damping ratio/flutter/half-power bandwidth method分类
通用工业技术引用本文复制引用
闫松,雷征,李祎,张志伟..整体式涡轮盘结构阻尼比精确测量方法[J].火箭推进,2025,51(2):125-131,7.基金项目
液体火箭发动机技术重点实验室基金(HTKJ2021KL011004) （HTKJ2021KL011004）
