转静干涉流场的激励特征与叶盘结构的共振设计

在对三维非定常转静干涉流场进行计算与分析的基础上,研究了转静干涉流场对叶盘结构激励的特征,包括尾流激励中的频率成分和空间成分, 以及这些特征成分的相对大小. 在此基础上,结合叶盘结构共振条件,总结并提出了从抑制共振的角度确定静子结构周期数的设计原则,即静子结构周期数的确定应使其产生的尾流激励的频率特征中不包含叶盘结构的频率成分,以及空间分布特征中不包含对应该频率模态节径的谐波成分.给出了基于转静干涉流场特征参数估算尾流激励主要频率成分和空间成分的公式, 使这一确定静子结构周期数的原则在设计阶段可方便实施.数值分析结果对这种估算公式的合理性进行了验证.结果表明:该公式不需对转静干涉三维非定常流场进行数值模拟, 即可对静子结构周期数的合理性(是否会引起共振)做出判断. 

Excitation characteristics of rotor/stator-interaction flow field and resonant design of bladed disk

Based on the computation and analysis of three-dimensional unsteady flow induced by rotor/stator-interaction, the characteristics of flow excitation to bladed disk were studied, including frequency-components and circumferential wave-components in the wake of stator. By combining the resonant condition of bladed disk, a design principle was given for determining the stator-structural period from the view of avoiding resonance, namely, the stator-structural period should ensure that in the wake excitation there was neither modal frequency-component of bladed disk nor circumferential wave-component corresponding to the nodal diameter of the bladed disk. The formula was given to predict frequency-components and circumferential wave-components in wake of stator, making it easier to determinate stator-structural period in design phase. It is shown by numerical analysis that this method can determinate the rationality (inducing the resonance or not) of stator-structural period without need of performing numerical simulation of three-dimensional unsteady flow induced by rotor/stator-interaction.