Accession Number:

ADA017073

Title:

Unsteady Surface Flow Behavior on a Cascade of Airfoils Oscillating Below Stall.

Descriptive Note:

Technical rept. Mar-Sep 75,

Corporate Author:

PURDUE UNIV LAFAYETTE IND PROJECT SQUID HEADQUARTERS

Personal Author(s):

• Carta,Franklin O.

Report Date:

1975-09-29

Pagination or Media Count:

65.0

Abstract:

Tests have been performed on a cascade of airfoils oscillating in pitch using hot films to detect unsteady changes in the flow over the suction surface. It was found that unsteady transition from laminar to turbulent flow propagates forward along the chord and that unsteady reattachment propagates rearward. At low incidence angle the turbulent flow region does not reach the leading edge, and at higher incidence angle the laminar flow region does not extend rearward beyond mid chord. Author

Descriptors:

• *Airfoils
• *Cascade structures
• Cascades(Fluid dynamics)
• Stalling
• Flutter
• Turbulent flow
• Vibration
• Boundary layer transition
• Free stream
• Laminar flow
• Pressure distribution
• Suction slots
• Leading edges
• Angle of attack
• Flow separation
• Transducers
• Oscillation

Subject Categories:

• Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE