COMPUTATIONAL INVESTIGATION OF ROTOR AEROACOUSTIC RESPONSE TO COMPLEX TURBULENT INFLOWS
Abstract
The ingestion of turbulent fow into a rotor is a significant source of noise in aeronautical, marine, automotive and wind energy applications. The current generation of rotor-noise models is of semi-empirical nature and ill-equipped to provide accurate predictions in realistic situations. We propose a computational study aimed at advancing predictive capabilities for and knowledge of rotor turbulence-ingestion noise under complex in ow conditions including pressure gradients, surface curvature, and transient disturbances. This is the computational component of a concerted eort being proposed that also includesexperimental studies at Virginia Tech (Professors William Devenport and Nathan Alexander) and analytical modeling at Florida Atlantic University (Professor Stewart Glegg).The proposed computational investigation consists of two major parts: (1) to complete the aeroacoustic analysis of a rotor ingesting an axisymmetric boundary layer on a body of revolution (BOR) started under the current grant, and extend this study to a non-axisymmetric low caused by a non-zero angle of attack of the BOR, and (2) to conduct investigations of the rotor aeroacoustic response to transient in low disturbances. The transient turbulence-ingestion noise study will be performed for a rotor partially immersed in a thick at-plate boundary layer with the transient disturbances generated by an upstream control surface. The computational approach is based on large-eddy simulation using anunstructured-mesh, nite-volume code with a sliding-interface capability in combination with the Ffowcs Williams-Hawkings equation, and will be enhanced with a capability to calculate the acoustic scattering by the BOR and control surfaces. Numerical results will be validated against experimental measurements and then used to elucidate the acoustic source mechanisms in relation to turbulence structures, evaluate the accuracy of noise prediction models under complex and transient in low conditions, and provide detailed input for model development.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 31, 2020
- Source ID
- N000142012688
Entities
People
- Meng Wang
Organizations
- Office of Naval Research
- United States Navy
- University of Notre Dame