A new optically index matched facility has been constructed to investigate tip flows in compressor-like settings. The blades of the one and a half stage compressor have the same geometry, but lower aspect ratio as the inlet guide vanes (IGVs) and the first stage of the low-speed axial compressor (LSAC) facility at NASA Glenn. With transparent blades and casings, the new setup enables unobstructed velocity measurements at any point within the tip region and is designed to facilitate direct measurements of effects of casing treatments on the flow structure. We start with a smooth endwall casing. High speed movies of cavitation and time-resolved PIV measurements have been used to characterize the location, trajectory, and behavior of the tip leakage vortex (TLV) for two flow rates, the lower one representing prestall conditions. Results of both methods show consistent trends. As the flow rate is reduced, TLV rollup occurs further upstream, and its initial orientation becomes more circumferential. At prestall conditions, the TLV is initially aligned slightly upstream of the rotor passage, and subsequently forced downstream. Within the passage, the TLV breaks up into a large number of vortex fragments, which occupy a broad area. Consequently, the cavitation in the TLV core disappears. With decreasing flow rate, this phenomenon becomes more abrupt, occurs further upstream, and the fragments occupy a larger area.
Visualization and Time-Resolved Particle Image Velocimetry Measurements of the Flow in the Tip Region of a Subsonic Compressor Rotor
Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received August 11, 2014; final manuscript received August 15, 2014; published online October 28, 2014. Editor: Ronald Bunker.
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
- Search Site
Tan, D., Li, Y., Wilkes, I., Miorini, R. L., and Katz, J. (October 28, 2014). "Visualization and Time-Resolved Particle Image Velocimetry Measurements of the Flow in the Tip Region of a Subsonic Compressor Rotor." ASME. J. Turbomach. April 2015; 137(4): 041007. https://doi.org/10.1115/1.4028433
Download citation file:
- Ris (Zotero)
- Reference Manager