Basic Studies of the Unsteady Flow Past High Angle of Attack Airfoils
Abstract
An experimental and numerical simulations have been carried out to study the unsteady flow past an impulsively started NACA 0012 airfoil at different angles of attack (O<alpha<45 deg.). A novel experimental technique, commonly referred to as Particle Image Displacement Velocimetry (PIDV), is successfully implemented to measure the instantaneous velocity fields. The velocity field is measured with sufficient accuracy so that the distribution of vorticity can be calculated. The unsteady separated flow fields generated by these airfoils contain large scale vortical structures such as; a primary vortex generated at the leading edge of the airfoil with secondary vortices upstream of it; a trailing vortex, and a vortex sheet type structure. The origins and time evolution of these structures are clearly depicted by the instantaneous velocity and vorticity fields. A random-walk vortex simulations of the full Navier-Stokes equations were performed as comparison. Keywords: Unsteady flows; High angle of attack airfoils; Particle image velocimetry; Vortex calculations.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 15, 1989
- Accession Number
- ADA210252
Entities
People
- Anjaneyulu Krothapalli
- Leon Van Dommelen
- Luiz Lourenco
Organizations
- Florida State University