Noise Due to the Interaction of Boundary Layer Turbulence with a Marine Propulsor or an Aircraft Compressor.
Abstract
The sound generated by the interaction of inlet boundary layer turbulence with a rotating blade row is investigated. To experimentally study this radiated sound, an existing aeroacoustic facility was modified to produce the inflows desired. The rotor was operated in air with different blade space-to-chord ratios, different flow coefficients and different anisotropic, nonhomogeneous turbulent inflows. The inflows ingested are: (1) natural boundary layer on hub and annulus wall, (2) a tripped boundary layer on the hub, and (3) a fully developed boundary layer on the hub. The turbulence intensities and length scales were altered by placing a grid at the inlet. The sound pressure level is found to be directly proportional to the turbulence intensity squared and inversely proportional to the ratio of axial length scale to blade spacing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 11, 1976
- Accession Number
- ADA040946
Entities
People
- B. Lakshminarayana
- D. E. Thompson
- Neil Moiseev
Organizations
- Pennsylvania State University