High Temperature Supersonic Jet Noise - Fundamental Studies and Control using Advanced Actuation Methods
Abstract
Understanding and controlling jet noise has been the focus of analytical, computational and experimental research for decades, however methods of measurably controlling-reducing jet noise in an efficient and robust manner remain evasive. Previous research has shown that coherent structures are one of the dominant sources of jet noise for both supersonic as well as subsonic jets. These structures are generally regarded as manifestations of the initial shear layer instabilities that originate at the nozzle exit. Under this effort, we addressed this problem with a multi-pronged approach to better understanding and controlling Jet Noise at realistic conditions. We developed a framework using optimal perturbation theory which predicts the most unstable modes that are expected to grow inside the nozzle. Such amplified perturbations are expected to be the source of large scale turbulent structures that develop in the jet shear layer contributing to noise from this source. Along a related but distinct path, we developed very high frequency actuators to directly introduce disturbances in the jet shear layer at frequencies that have been shown to suppress turbulence (Zaman and Hussain3) and hence may lead to jet noise suppression.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 24, 2016
- Accession Number
- AD1017166
Entities
People
- Chiang Shih
- Farrukh S. Alvi
Organizations
- Florida A&M University