Executive Summary : | Turbomachines are essential devices for power generation and propulsion, and improving their efficiency is crucial to minimize energy consumption. Thin blades in compressors can be prone to vibrations, which can be either forced or self-excited. This interaction between fluid and structure can lead to instability called "Flutter" and Limit Cycle Oscillations (LCOs), resulting in catastrophic failure. Designers solve these issues by making modifications to the structure, such as mass-balance, moving the elastic/flexural axis, and increasing the torsional rigidity.
Flutter/LCOs might reappear in the service life of the turbomachine due to wear and tear. To address these issues, next-generation turbomachines can use Active Flutter Suppression (AFS) technology, which can be activated or deactivated based on the turbomachine's life. The current proposal aims to evaluate the performance of AFS for compressor cascade using steady/unsteady blowing. The aeroelastic compressor cascade will be instrumented with surface pressure measurements, accelerometers for structure motion, and a hot-wire anemometer for unsteady wake behavior. Data from all sensors will be recorded using a computer-based data acquisition system, helping to understand flow dynamics during flutter/LCOs and the performance of AFS. The compressed air required for steady/unsteady blowing will be controlled using a flow circuit. Understanding flow dynamics during flutter/LCOs and after AFS activation is expected to aid in developing models for predicting flutter/LCOs. |