Drag Characteristics for a Compliant Surface Airfoil.
Abstract
As part of a program to investigate the feasibility of reducing aerodynamic skin-friction drag by the use of compliant coatings, a detailed wind-tunnel study was made to determine the drag characteristics of a compliant coating on a airfoil. The compliant surface was constructed with different thickness (0.001 to 0.025 inch) of polyvinyl-chloride (PVC) membrane backed by a 3/16 to 6/16 inch damping layer of polyurethane foam (40 PPI). The foam was bonded to specially designed airfoils to form NACA 0009 airfoils. Hard surface NACA 0009 airfoils were also constructed. A reduction of skin friction drag was recorded in order to be sure the drag reduction did not come from the shifting of the transition line, both experimental (china-clay) and theoretical (von-Karman-Pohlhausen) methods were used to determine the transition point. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1971
- Accession Number
- AD0729921
Entities
People
- Humphrey H. Chu
Organizations
- University of Oklahoma