Propagation of acoustic disturbances in transonic flow fields of lifting wings
Abstract
The propagation of small disturbances in the vicinity of transonic flutter surfaces with mixed sub-/supersonic regions is investigated based on the approximation of geometrical acoustics. Waves, rays, and the spatial density distribution of the dissipated disturbance energy are numericaly calculated using a system of 18 differential equations. The effects of various two and three-dimensional fields, of the source locus, and of reflections on the wing surface are investigated. The results of the acoustic theory are used to derive a general influence function for sources of disturbance in arbitrary transonic fields. This function represents a step toward a surface panel method to calculate unsteady transonic flows. The acoustic results are compared with measured unsteady pressure distributions on oscillating transonic wings and with results of a numerical field panel method.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- February 1988
- Bibcode:
- 1988PhDT.........3V
- Keywords:
-
- Acoustic Instability;
- Geometrical Acoustics;
- Sound Waves;
- Transonic Flutter;
- Acoustic Propagation;
- Differential Equations;
- Structural Vibration;
- Transonic Flow;
- Wave Propagation;
- Acoustics