Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 226
Book Description
Aerodynamic Performance Investigation of Advanced Mechanical Suppressor and Ejector Nozzle Concepts for Jet Noise Reduction
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 226
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 226
Book Description
Aerodynamic Performance Investigation of Advanced Mechanical Suppressor and Ejector Nozzle Concepts for Jet ....
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
NASA Reference Publication
Author:
Publisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 460
Book Description
Publisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 460
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1126
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1126
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Simulated Flight Acoustic Investigation of Treated Ejector Effectiveness on Advanced Mechanical Suppresors for High Velocity Jet Noise Reduction
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 424
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 424
Book Description
Simulated Flight Acoustic Investigtion of Treated Ejector Effectiveness on Advanced Mechanical Suppressors for High Velocity Jet Noise Reduction
Author: John F. Brausch
Publisher:
ISBN:
Category :
Languages : en
Pages : 408
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 408
Book Description
Aerodynamic and Acoustic Tests of Duct-burning Turbofan Exhaust Nozzles
Author: Hilary Kozlowski
Publisher:
ISBN:
Category :
Languages : en
Pages : 148
Book Description
The static aerodynamic and acoustic characteristics of duct-burning turbofan (DBTF) exhaust nozzles are established. Scale models, having a total area equivalent to a 0.127 m diameter convergent nozzle, simulating unsuppressed coannular nozzles and mechanically suppressed nozzles with and without ejectors (hardwall and acoustically treated) were tested in a quiescent environment. The ratio of fan to primary area was varied from 0.75 to 1.2. Far field acoustic data, perceived noise levels, and thrust measurements were obtained for 417 test conditions. Pressure ratios were varied from 1.3 to 4.1 in the fan stream and from 1.53 to 2.5 in the primary stream. Total temperature varied from 395 to 1090 K in both streams. Jet noise reductions relative to synthesized prediction from 8 PNdB (with the unsuppressed coannular nozzle) to 15 PNdB (with a mechanically suppressed configuration) were observed at conditions typical of engines being considered under the Advanced Supersonic Technology program. The inherent suppression characteristic of the unsuppressed coannular nozzle is related to the rapid mixing in the jet wake caused by the velocity profiles associated with the DBTF. Since this can be achieved without a mechanical suppressor, significant reductions in aircraft weight or noise footprint can be realized.
Publisher:
ISBN:
Category :
Languages : en
Pages : 148
Book Description
The static aerodynamic and acoustic characteristics of duct-burning turbofan (DBTF) exhaust nozzles are established. Scale models, having a total area equivalent to a 0.127 m diameter convergent nozzle, simulating unsuppressed coannular nozzles and mechanically suppressed nozzles with and without ejectors (hardwall and acoustically treated) were tested in a quiescent environment. The ratio of fan to primary area was varied from 0.75 to 1.2. Far field acoustic data, perceived noise levels, and thrust measurements were obtained for 417 test conditions. Pressure ratios were varied from 1.3 to 4.1 in the fan stream and from 1.53 to 2.5 in the primary stream. Total temperature varied from 395 to 1090 K in both streams. Jet noise reductions relative to synthesized prediction from 8 PNdB (with the unsuppressed coannular nozzle) to 15 PNdB (with a mechanically suppressed configuration) were observed at conditions typical of engines being considered under the Advanced Supersonic Technology program. The inherent suppression characteristic of the unsuppressed coannular nozzle is related to the rapid mixing in the jet wake caused by the velocity profiles associated with the DBTF. Since this can be achieved without a mechanical suppressor, significant reductions in aircraft weight or noise footprint can be realized.
A Survey of Challenges in Aerodynamic Exhaust Nozzle Technology for Aerospace Propulsion Applications
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721531660
Category :
Languages : en
Pages : 26
Book Description
The current paper discusses aerodynamic exhaust nozzle technology challenges for aircraft and space propulsion systems. Technology advances in computational and experimental methods have led to more accurate design and analysis tools, but many major challenges continue to exist in nozzle performance, jet noise and weight reduction. New generations of aircraft and space vehicle concepts dictate that exhaust nozzles have optimum performance, low weight and acceptable noise signatures. Numerous innovative nozzle concepts have been proposed for advanced subsonic, supersonic and hypersonic vehicle configurations such as ejector, mixer-ejector, plug, single expansion ramp, altitude compensating, lobed and chevron nozzles. This paper will discuss the technology barriers that exist for exhaust nozzles as well as current research efforts in place to address the barriers. Shyne, Rickey J. Glenn Research Center NASA/TM-2002-211977, NAS 1.15:211977, E-13646
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721531660
Category :
Languages : en
Pages : 26
Book Description
The current paper discusses aerodynamic exhaust nozzle technology challenges for aircraft and space propulsion systems. Technology advances in computational and experimental methods have led to more accurate design and analysis tools, but many major challenges continue to exist in nozzle performance, jet noise and weight reduction. New generations of aircraft and space vehicle concepts dictate that exhaust nozzles have optimum performance, low weight and acceptable noise signatures. Numerous innovative nozzle concepts have been proposed for advanced subsonic, supersonic and hypersonic vehicle configurations such as ejector, mixer-ejector, plug, single expansion ramp, altitude compensating, lobed and chevron nozzles. This paper will discuss the technology barriers that exist for exhaust nozzles as well as current research efforts in place to address the barriers. Shyne, Rickey J. Glenn Research Center NASA/TM-2002-211977, NAS 1.15:211977, E-13646
NASA Technical Memorandum
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 492
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 492
Book Description
Transportation... Weekly Government Abstracts
Author:
Publisher:
ISBN:
Category : Transportation
Languages : en
Pages : 630
Book Description
Publisher:
ISBN:
Category : Transportation
Languages : en
Pages : 630
Book Description