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Ducted-fan engine acoustic predictions using a navier-stokes code
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Biedron, R. T. Rumsey, C. L. Farassat, F. Spence, P. L. |
| Copyright Year | 1998 |
| Description | A Navier-Stokes computer code is used to predict one of the ducted-fan engine acoustic modes that results from rotor-wake/stator-blade interaction. A patched sliding-zone interface is employed to pass information between the moving rotor row and the stationary stator row. The code produces averaged aerodynamic results downstream of the rotor that agree well with a widely used average-passage code. The acoustic mode of interest is generated successfully by the code and is propagated well upstream of the rotor; temporal and spatial numerical resolution are fine enough such that attenuation of the signal is small. Two acoustic codes are used to find the far-field noise. Near-field propagation is computed by using Eversman's wave envelope code, which is based on a finite-element model. Propagation to the far field is accomplished by using the Kirchhoff formula for moving surfaces with the results of the wave envelope code as input data. Comparison of measured and computed far-field noise levels show fair agreement in the range of directivity angles where the peak radiation lobes from the inlet are observed. Although only a single acoustic mode is targeted in this study, the main conclusion is a proof-of-concept: Navier-Stokes codes can be used both to generate and propagate rotor/stator acoustic modes forward through an engine, where the results can be coupled to other far-field noise prediction codes. |
| File Size | 1764242 |
| Page Count | 40 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20040110325 |
| Archival Resource Key | ark:/13960/t7np70s7v |
| Language | English |
| Publisher Date | 1998-06-01 |
| Access Restriction | Open |
| Subject Keyword | Aircraft Propulsion And Power Navier-stokes Equation Engine Noise Jet Aircraft Noise Rotor Stator Interactions Ducted Fan Engines Aeroacoustics Noise Prediction Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
