Author: United States. National Aeronautics and Space Administration
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
DEVELOPMENT AND DEMONSTRATION OF ACTIVE NOISE CONTROL CONCEPTS FINAL REPORT... NASA
Author: United States. National Aeronautics and Space Administration
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Development and Demonstration of Active Noise Control Concepts
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721094202
Category :
Languages : en
Pages : 154
Book Description
This report details design methods for and feasibility of an Active Noise Control (ANC) system using flush-wall-mounted sensors and actuators to reduce turbofan engine rotor-stator interaction noise. ANC concepts capable of suppressing discrete-tone spinning modes containing several cut-on radial mode were identified, developed analytically, and evaluated. Separate ANC systems that suppressed at least three radial modes in a cylindrical inlet duct and three radial modes in an exhaust annulus were developed. These designs resulted in inlet duct and exhaust duct tests that were performed at NASA on the 4-ft ANC Fan in the NASA Glenn AAPL facility. Effective suppression of 2-BPF spinning mode m = 2 tone noise was achieved over a range of fan speeds 1800 to 2450 rpm, where up to 4 radials were present. In the inlet duct, up to 12 dB reduction was obtained for 3 radial modes, and up to 4 dB was obtained with 4 radial modes. In the exhaust duct, up to 15 dB PWL reduction was obtained with either two or three radial modes present. Thus, the ability to suppress multiple radial modes for tones in both the inlet and exhaust ducts has been successfully demonstrated. Implications of ANC system design requirements on installation and system integration issues for ANC systems capable of suppressing higher order radial mode content when applied to a 767 using twin CF6 engines were evaluated analytically. The analytical results indicated an ANC system must be part of an integrated design to be effective. Kraft, R. and Hu, Z. and Sommerfeldt, S. and Walker, B. and Hersh, A. and Luo, H. and Spencer, M. and Hallman, D. and Mitchell, C. and Sutliff, D. Glenn Research Center NAS3-27720; RTOP 522-81-11
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721094202
Category :
Languages : en
Pages : 154
Book Description
This report details design methods for and feasibility of an Active Noise Control (ANC) system using flush-wall-mounted sensors and actuators to reduce turbofan engine rotor-stator interaction noise. ANC concepts capable of suppressing discrete-tone spinning modes containing several cut-on radial mode were identified, developed analytically, and evaluated. Separate ANC systems that suppressed at least three radial modes in a cylindrical inlet duct and three radial modes in an exhaust annulus were developed. These designs resulted in inlet duct and exhaust duct tests that were performed at NASA on the 4-ft ANC Fan in the NASA Glenn AAPL facility. Effective suppression of 2-BPF spinning mode m = 2 tone noise was achieved over a range of fan speeds 1800 to 2450 rpm, where up to 4 radials were present. In the inlet duct, up to 12 dB reduction was obtained for 3 radial modes, and up to 4 dB was obtained with 4 radial modes. In the exhaust duct, up to 15 dB PWL reduction was obtained with either two or three radial modes present. Thus, the ability to suppress multiple radial modes for tones in both the inlet and exhaust ducts has been successfully demonstrated. Implications of ANC system design requirements on installation and system integration issues for ANC systems capable of suppressing higher order radial mode content when applied to a 767 using twin CF6 engines were evaluated analytically. The analytical results indicated an ANC system must be part of an integrated design to be effective. Kraft, R. and Hu, Z. and Sommerfeldt, S. and Walker, B. and Hersh, A. and Luo, H. and Spencer, M. and Hallman, D. and Mitchell, C. and Sutliff, D. Glenn Research Center NAS3-27720; RTOP 522-81-11
Development and Demonstration of Active Noise Control Concepts
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 308
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 308
Book Description
Federal Aircraft Noise Research, Development and Demonstration Programs: FY73-FY75
Author: Interagency Aircraft Noise Research Panel
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 236
Book Description
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 236
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 836
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 836
Book Description
Monthly Catalogue, United States Public Documents
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1068
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1068
Book Description
Monthly Catalog of United States Government Publications
Author:
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ISBN:
Category : Government publications
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages :
Book Description
Government Reports Announcements & Index
Author:
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ISBN:
Category : Science
Languages : en
Pages : 1464
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1464
Book Description
Space Station Systems
Author:
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ISBN:
Category : Space stations
Languages : en
Pages : 606
Book Description
Publisher:
ISBN:
Category : Space stations
Languages : en
Pages : 606
Book Description
Commerce Business Daily
Author:
Publisher:
ISBN:
Category : Government purchasing
Languages : en
Pages : 1902
Book Description
Publisher:
ISBN:
Category : Government purchasing
Languages : en
Pages : 1902
Book Description