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Experimental Noise Investigation of Model Nozzles.

AD610256

Publication Date	1964
Personal Author	Pernet, D. F.
Page Count	2
Abstract	Far field sound pressure levels were measured in an anechoic room for noise generated by cold air flow through a wide variety of small nozzle configurations. These nozzles included converging, converging-diverging, annular plug, annular center core flow, and ejector types. The results are examined in terms of mass flow and acoustic power performance. Thrust determinations were made for selected nozzles showing good acoustic performance, permitting an ultimate evaluation of their acoustic performance in terms of their thrust performance. Optimized nozzles from each of four nozzle configurations are recommended for a full-scale evaluation. These are a plug, a center core flow, a converging-diverging, and a converging-diverging plug nozzle. The noise generated by hot air flow through a converging nozzle was determined, enabling only partial corroboration of the scaling technique developed in a previous study. One of the recommended nozzle types, the plug nozzle, was investigated under hot flow conditions and its acoustic performance was found to remain superior to that of a converging nozzle. (Author)
Keywords	JET PLANE NOISE EXHAUST NOZZLES ACOUSTICS NOZZLE GAS FLOW SOUND PRESSURE THRUST ANECHOIC CHAMBERS MODELS (SIMULATIONS) JET ENGINE NOISE MATHEMATICAL ANALYSIS
Corporate Authors	Iit Research Inst Chicago Ill
Document Type	Technical Report
Title Note	Rept. for Nov 63-Dec 64.
NTIS Issue Number	196505
Contract Number	AF33 615 1164

Experimental Noise Investigation of Model Nozzles.

Experimental Noise Investigation of Model Nozzles.
AD610256

Publication Date	1964
Personal Author	Pernet, D. F.
Page Count	2
Abstract	Far field sound pressure levels were measured in an anechoic room for noise generated by cold air flow through a wide variety of small nozzle configurations. These nozzles included converging, converging-diverging, annular plug, annular center core flow, and ejector types. The results are examined in terms of mass flow and acoustic power performance. Thrust determinations were made for selected nozzles showing good acoustic performance, permitting an ultimate evaluation of their acoustic performance in terms of their thrust performance. Optimized nozzles from each of four nozzle configurations are recommended for a full-scale evaluation. These are a plug, a center core flow, a converging-diverging, and a converging-diverging plug nozzle. The noise generated by hot air flow through a converging nozzle was determined, enabling only partial corroboration of the scaling technique developed in a previous study. One of the recommended nozzle types, the plug nozzle, was investigated under hot flow conditions and its acoustic performance was found to remain superior to that of a converging nozzle. (Author)
Keywords	JET PLANE NOISE EXHAUST NOZZLES ACOUSTICS NOZZLE GAS FLOW SOUND PRESSURE THRUST ANECHOIC CHAMBERS MODELS (SIMULATIONS) JET ENGINE NOISE MATHEMATICAL ANALYSIS
Corporate Authors	Iit Research Inst Chicago Ill
Document Type	Technical Report
Title Note	Rept. for Nov 63-Dec 64.
NTIS Issue Number	196505
Contract Number	AF33 615 1164