Oscillating cascade aerodynamics at large mean incidence
- NASA Lewis Research Center, Cleveland, OH (United States)
- Univ. of California, Davis, CA (United States). Dept. of Mechanical and Aeronautical Engineering
- Pratt and Whitney, West Palm Beach, FL (United States)
The aerodynamics of a cascade of airfoils oscillating in torsion about the midchord is investigated experimentally at a large mean incidence angle and, for reference, at a low mean incidence angle. The airfoil section is representative of a modern, low-aspect-ratio, fan blade tip section. Time-dependent airfoil surface pressure measurements were made for reduced frequencies of up to 1.2 for out-of-phase oscillations at a Mach number of 0.5 and chordal incidence angles of 0 and 10 deg; the Reynolds number was 0.9 {times} 10{sup 6}. For the 10 deg chordal incidence angle, a separation bubble formed at the leading edge of the suction surface. The separated flow field was found to have a dramatic effect on the chordwise distribution of the unsteady pressure. In this region, substantial deviations from the attached flow data were found, with the deviations becoming less apparent in the aft region of the airfoil for all reduced frequencies. In particular, near the leading edge the separated flow had a strong destabilizing influence while the attached flow had a strong stabilizing influence.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 290066
- Report Number(s):
- CONF-960608-; ISSN 0889-504X; TRN: IM9834%%208
- Journal Information:
- Journal of Turbomachinery, Vol. 120, Issue 1; Conference: 41. American Society of Mechanical Engineers (ASME) international gas turbine and aeroengine congress and exposition, Birmingham (United Kingdom), 10-13 Jun 1996; Other Information: PBD: Jan 1998
- Country of Publication:
- United States
- Language:
- English
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