Abstract: In order to uncover the effect mechanics of high-low altitude on aeroelasticity stability of compres. sor，blades flutter characteristics in different altitudes were investigated through numerical study based on har.monic balance technique and energy method. Results show that，for the 2nd mode on the near stall point，the mini. mum aerodynamic damping of blades corresponding to nodal diameter has the value of 1 on the ground，while the value of 2 in high altitude. The minimum values of aerodynamic damping coefficient(LogDec)of blades were 0.3460%，0.2168% and 0.5460%，0.4521%，respectively，in high and low altitude for the first two modes on the near stall point，nevertheless，at the blade tip the local LogDec on the ground is less than this in high altitude. Theunsteady pressure perturbations present various time-space shapes with different working altitudes at the bladetip corresponding to the first mode on the near stall point，which results in a huge discrepancy of local work sum. mation.

Key words: Blade flutter；Unsteady flow；High-low altitude；Energy method

摘要： 为了揭示高低空环境对压气机气动弹性稳定性的影响机理，采用谐波平衡技术和能量法对叶片在不同工作高度下的颤振特性进行了数值研究。结果表明:近失速二阶模态下叶片在地面和高空于不同的波节数 1和2时达到最小气动阻尼状态；近失速前两阶模态下高低空叶片的气动阻尼系数(LogDec)最小值分别为 0.5460%，0.4521%和 0.3460%，0.2168%，但叶尖处地面的当地 LogDec小于高空值；对于近失速一阶模态，叶片尖部的非定常压力脉动随着工作高度的变化呈现出不同的时空形态，从而导致当地积累功存在较大差异。

关键词: 叶片颤振；非定常流；高低空；能量法