Author: Willard D. Coles
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 652
Book Description
Several noise suppressors consisting of combinations of mixing nozzles and ejectors were tested on two full-scale turbojet engines. Maximum sound pressure level reductions of 12 decibels and sound power level reductions of 8 decibels were obtained. The ejectors provided 3 to 5 decibels of the sound power reduction. The effects of ejector dimensions on noise suppression and engine performance were investigated. Ejector lengths of approximately 2.0 standard nozzle diameters and ejector diameters larger than 1.6 standard nozzle diameters provided the greatest additional noise reduction to that obtained with the mixing nozzles alone. The ejector can restore the static thrust loss caused by use of the mixing nozzle or can provide static-thrust augmentation.
Turbojet Engine Noise Reduction with Mixing Nozzle-ejector Combinations
Author: Willard D. Coles
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 652
Book Description
Several noise suppressors consisting of combinations of mixing nozzles and ejectors were tested on two full-scale turbojet engines. Maximum sound pressure level reductions of 12 decibels and sound power level reductions of 8 decibels were obtained. The ejectors provided 3 to 5 decibels of the sound power reduction. The effects of ejector dimensions on noise suppression and engine performance were investigated. Ejector lengths of approximately 2.0 standard nozzle diameters and ejector diameters larger than 1.6 standard nozzle diameters provided the greatest additional noise reduction to that obtained with the mixing nozzles alone. The ejector can restore the static thrust loss caused by use of the mixing nozzle or can provide static-thrust augmentation.
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 652
Book Description
Several noise suppressors consisting of combinations of mixing nozzles and ejectors were tested on two full-scale turbojet engines. Maximum sound pressure level reductions of 12 decibels and sound power level reductions of 8 decibels were obtained. The ejectors provided 3 to 5 decibels of the sound power reduction. The effects of ejector dimensions on noise suppression and engine performance were investigated. Ejector lengths of approximately 2.0 standard nozzle diameters and ejector diameters larger than 1.6 standard nozzle diameters provided the greatest additional noise reduction to that obtained with the mixing nozzles alone. The ejector can restore the static thrust loss caused by use of the mixing nozzle or can provide static-thrust augmentation.
Technical Note - National Advisory Committee for Aeronautics
Author: United States. National Advisory Committee for Aeronautics
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1160
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1160
Book Description
Fundamental Study of Jet Noise Generation and Suppression
U.S. Government Research Reports
Effect of Multiple-nozzle Geometry on Jet Noise Generation
Author: Vern G. Rollin
Publisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 22
Book Description
Publisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 22
Book Description
NASA Memorandum
NASA Technical Note
NASA Memorandum
Author: United States. National Aeronautics and Space Administration
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 26
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 26
Book Description
NASA Technical Report
The Theory of Diffusion in Strained Systems
Author: Louis A. Girifalco
Publisher:
ISBN:
Category : Crystals
Languages : en
Pages : 1082
Book Description
A general theory of solid-state diffusion in strained systems is developed on a molecular-kinetic basis. The theory predicts that for simple strains the diffusion coefficient is an exponential function of the lattice parameter and that the rate of change of the diffusion coefficient with strain is linearly related to the interatomic forces. It has also been shown that for plastic flow the diffusion coefficient is a linear function of strain rate. All the conclusions are confirmed by the data available in the literature.
Publisher:
ISBN:
Category : Crystals
Languages : en
Pages : 1082
Book Description
A general theory of solid-state diffusion in strained systems is developed on a molecular-kinetic basis. The theory predicts that for simple strains the diffusion coefficient is an exponential function of the lattice parameter and that the rate of change of the diffusion coefficient with strain is linearly related to the interatomic forces. It has also been shown that for plastic flow the diffusion coefficient is a linear function of strain rate. All the conclusions are confirmed by the data available in the literature.