Noise Generation due to Turbulent Flow Over Surface Slots
Abstract
An experimental investigation was conducted which addressed noise generation mechanisms due to turbulent boundary layer flow over a series of surface slots. The objectives of the experiment were to identify localized radiated noise sources from the slots and to relate these noise sources to interactions between near-wall turbulent boundary layer fluid and the slots. Radiated noise from an assembly of angled slats mounted in a flat plate was measured under various inflow boundary layer conditions, which were quantified from mean streamwise velocity measurements. In addition, higher order turbulence statistics were provided by high resolution DPIV measurements made at Rutgers University. Results of the radiated noise studies indicated that noise generated due to turbulent flow over the slats scaled with outer flow variables and that this noise was predominantly produced from the forward half of the slat assembly. Based on the flow measurements, it is believed that this effect is due to increased near-wall velocities in the forward half of the slat assembly, resulting in stronger interactions between near-wall fluid and the slats and ultimately increased Reynolds stress gradients.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 15, 1998
- Source ID
- 10.1115/imece1998-0501
Entities
People
- Lisa M. Grega
- Theodore M. Farabee
- Timothy Wei
Organizations
- Naval Surface Warfare Center
- Rutgers University