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Design selection and analysis of a swept and leaned stator concept
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Envia, Edmane Nallasamy, M. |
| Copyright Year | 1998 |
| Description | This report describes a theoretical design and analysis study of the benefits of vane sweep and lean for reducing rotor- stator interaction tone noise. It is shown that the kinematic relationship between the rotor wakes and stator vanes is the principal factor in determining the achievable noise reductions. Vane sweep and lean control rotor wake skewing as seen by the stator vanes and hence influence the number of wake intersections per vane. An increase in the number of intersections reduces noise levels. Hence, to reduce rotor-stator noise, van sweep and lean must be chosen in such a way as to increase wake intersections per vane. A simple design rule is thus proposed which requires a sweep configuration that puts the vane tip downstream of its root and a vane lean that is in the direction of the rotor rotation. A detailed comparison of the predicted and measured noise reductions for a swept and leaned stator is then carried out. Overall, these comparisons show that the predicted benefits of a swept and leaned stator are in good agreement, qualitative as well as quantitative, with the measured reductions for the fan speeds relevant to noise certification procedure. Furthermore, the results also demonstrate the validity of design criterion and the theoretical tools used in this study. |
| File Size | 1468373 |
| Page Count | 22 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19990018027 |
| Archival Resource Key | ark:/13960/t7xm37x7t |
| Language | English |
| Publisher Date | 1998-12-01 |
| Access Restriction | Open |
| Subject Keyword | Acoustics Noise Reduction Noise Intensity Rotors Wakes Vanes Stators Aerodynamic Noise Design Analysis Fan Blades Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
