Accession Number:

ADA205206

Title:

Comparison of Boundary Layer Trips of Disk and Grit Types on Airfoil Performance at Transonic Speeds

Descriptive Note:

Corporate Author:

NATIONAL AERONAUTICAL ESTABLISHMENT OTTAWA (ONTARIO)

Personal Author(s):

Report Date:

1988-12-01

Pagination or Media Count:

40.0

Abstract:

The effects on aerodynamic performance of a supercritical airfoil applying disk or grit tripping for boundary layer transition has been investigated for a typical supercritical airfoil at transonic speeds. It is observed that by allowing the laminar flow passing through the space between the disks, transition takes place a short distance downstream from the disk trip line. The boundary layer developed downstream from disk trip is therefore slightly thinner than that from a grit trip. The vortex generating mechanism of the disks may also enhance this development. This small difference has negligible effect on aerodynamics of the airfoil at low lift. However, at high lift, the difference in boundary layer developments is amplified by the strong shock wave and the severe adverse pressure gradient. The thinner and more energetic boundary layer induced by the disk trip will yield higher lift, lower drag and higher trailing edge pressure. Canada.

Subject Categories:

  • Aerodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE