Experimental study of tip clearance losses and noise in axial turbomachines and their reduction
- BMW Rolls-Royce Aeroengines, Dahlewitz (Germany)
- Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Berlin (Germany)
An experimental study is described to investigate the negative effects of the tip clearance gap on the aerodynamic and acoustic performance of axial turbomachines. In addition to the increased broadband levels reported in the literature when the tip clearance is enlarged, significant level increases were observed within narrow frequency bands below the blade passing frequency. Measurements of the pressure and velocity fluctuations in the vicinity of the blade tips reveal that the tip clearance noise is associated with a rotating flow instability at the blade tip, which in turn is only present under reversed flow conditions in the tip clearance gap. A turbulence generator inserted into the tip clearance gap is found to be effective in eliminating the tip clearance noise and in improving the aerodynamic performance.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 516715
- Journal Information:
- Journal of Turbomachinery, Vol. 119, Issue 3; Other Information: PBD: Jul 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Investigation of tip clearance phenomena in an axial compressor cascade using Euler and Navier--Stokes procedures
The effect of tip clearance on a swept transonic compressor rotor