Mechanisms and Active Control of Jet-Induced Noise

• Applicant: Professor Dr.-Ing. Ulrich Rist
• Subject Area: Fluid Mechanics
• Term: from 2003 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5470251

This sub-project aims at providing reference data for the noise produced by the shear (or mixing) layers of an aircraft-engine jet. Careful, high-order accurate direct numerical and large-eddy simulations (DNS/LES) are used to simulate the shear-layer flow-field with its instabilities, dynamical large-scale structures, turbulence, and noise generation. The data will be used for performing investigations on far-field noise prediction, with validation of sound propagation methodologies and schemes in the near- and in the medium field by the other sub-projects. The ultimate aim however consists of investigations of the sound generation mechanisms and their possible control. To this end simulation results will be given to the French partner at IMFT (Toulouse) where they will serve as initial Kondition for solving an adjoint problem for noise identification: this will allow insight into the fundamental mechanisms of noise generation. Finally, optimal control theory will be employed to find the most appropriate means for reducing noise, with actuators situated as close as possible to the noise source.

• DFG Programme: Research Units
• Subproject of: FOR 508: Noise Generation in Turbulent Flows
• International Connection: France
• Participating Persons: Christophe Airiau; Dr.-Ing. Markus J. Kloker