Experimental Investigation of Shock-Cell Noise Reduction for Single Stream Nozzles in Simulated FlightSeven single stream model nozzles were tested in the Anechoic Free-Jet Acoustic Test Facility to evaluate the effectiveness of convergent divergent (C-D) flowpaths in the reduction of shock-cell noise under both static and mulated flight conditions. The test nozzles included a baseline convergent circular nozzle, a C-D circular nozzle, a convergent annular plug nozzle, a C-D annular plug nozzle, a convergent multi-element suppressor plug nozzle, and a C-D multi-element suppressor plug nozzle. Diagnostic flow visualization with a shadowgraph and aerodynamic plume measurements with a laser velocimeter were performed with the test nozzles. A theory of shock-cell noise for annular plug nozzles with shock-cells in the vicinity of the plug was developed. The benefit of these C-D nozzles was observed over a broad range of pressure ratiosin the vicinity of their design conditions. At the C-D design condition, the C-D annual nozzle was found to be free of shock-cells on the plug.
Document ID
19850005241
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Yamamoto, K. (General Electric Co. Cincinnati, OH, United States)
Brausch, J. F. (General Electric Co. Cincinnati, OH, United States)
Balsa, T. F. (General Electric Co. Cincinnati, OH, United States)
Janardan, B. A. (General Electric Co. Cincinnati, OH, United States)
Knott, P. R. (General Electric Co. Cincinnati, OH, United States)