Experiments on the Receptivity of Transient Disturbances to Surface Roughness and Freestream Turbulence
Abstract
Transient growth is a boundary-layer instability mechanism that leads to algebraic growth of disturbances generated by surface roughness and freestream turbulence. An earlier research program verified that stationary, roughness-induced disturbances undergo transient growth but that these disturbances are sub-optimal and depend critically on the details of the receptivity process. This project seeks to provide a more complete understanding of the receptivity of transient disturbances to regular and random surface roughness as well as freestream turbulence. This objective is pursued through three separate tracks. First, a technique is developed to permit a rigorous decomposition of measured steady disturbances across the continuous spectrum of Orr-Sommerfeld/Squire eigenmodes. Second, the receptivity and transient growth of steady disturbances generated by quasi-random distributed surface roughness is investigated. Third, transient disturbances generated by controlled freestream turbulence are to be investigated.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2008
- Accession Number
- ADA476059
Entities
People
- Edward B. White
Organizations
- Case Western Reserve University