Prediction of acoustic resonance in a multistage high-speed axial compressor

多级高速轴流压缩机中声共振的预测

• 批准号: 468461660
• 负责人: Professor Dr.-Ing. Jörg Seume
• 金额: --
• 依托单位: Institut für Turbomaschinen und Fluid-Dynamik (TFD)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/468461660?language=en
• 关键词: Prediction; acoustic; resonance; multistage; speed

Economic and regulatory requirements for high operational flexibility of jet engines and power plants lead to more frequent off-design operation of turbomachinery components. Regarding operating stability, the compressor constitutes the most critical and challenging component in these turbomachines. Besides the well-known and intensely investigated aerodynamic instabilities of surge, rotating stall, and rotating instability, high pressure fluctuations have been identified as acoustic resonance in high-speed and high-pressure axial compressors at specific off-design operating points. Recent research shows that acoustic resonance can excite mechanical vibrations, which might result in severe blade damage or immediately fatal structural failure. In addition, research shows that acoustic resonances can shift the stability limit to higher mass flow rates by triggering rotating stall and surge. As several industrial producers of turbomachinery have experienced acoustic resonances there is considerable need for the understanding and characterization on the physical mechanism of this phenomenon for future design processes. First approaches by the applicant and his coworkers have led to two models to predict and characterize acoustic resonance, but data of these phenomena have rarely been reported in open literature. Therefore, validation of these models is necessary. To this end, improved physical understanding of the formation mechanism of the standing waves and of the excitation mechanisms is essential. The objective of the proposed project is to give further insights into the excitation mechanism and the resonance conditions in multi-stage axial compressors. Extensive simultaneous measurements of the tip leakage flow and the resonant acoustic field are carried out for the first time in a high-speed multistage axial compressor, which approximates realistic machine conditions. Based on the highly accurate measurements and numerical simulations, validation and calibration of the prediction models will be performed, which will lead to an approach to predict the occurrence of acoustic resonance.

对喷气发动机和动力装置的高操作灵活性的经济和法规要求导致发动机部件的更频繁的非设计操作。关于操作稳定性，压缩机构成了这些机组中最关键和最具挑战性的部件。除了众所周知的和深入研究的喘振、旋转失速和旋转不稳定性的空气动力学不稳定性之外，高压波动已经被确定为在特定的非设计操作点处的高速和高压轴流压气机中的声共振。最近的研究表明，声共振可以激发机械振动，这可能导致严重的叶片损坏或立即致命的结构故障。此外，研究表明，声共振可以通过触发旋转失速和喘振将稳定性极限转移到更高的质量流率。由于几个工业生产商的声共振的经验，有相当大的需要了解和表征的物理机制，这种现象的未来设计过程。申请人及其同事的第一种方法已经产生了两种模型来预测和表征声共振，但是这些现象的数据很少在公开文献中报道。因此，对这些模型进行验证是必要的。为此，必须改进对驻波的形成机制和激发机制的物理理解。该项目的目的是进一步了解多级轴流压气机的激励机制和共振条件。首次在一台高速多级轴流压气机中对叶尖泄漏流和共振声场进行了广泛的同时测量，该测量接近于实际的机器条件。基于高精度的测量和数值模拟，将执行预测模型的验证和校准，这将导致一种方法来预测声共振的发生。