Author: Roy K. Amiet
Publisher:
ISBN:
Category :
Languages : en
Pages : 42
Book Description
Noise Produced by Turbulent Flow Into a Rotor: Theory Manual for Noise Calculation
Noise Produced by Turbulent Flow Into a Rotor
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722414290
Category :
Languages : en
Pages : 36
Book Description
An analysis is presented for the calculation of noise produced by turbulent flow into a helicopter rotor. The method is based on the analysis of Amiet for the sound produced by an airfoil moving in rectilinear motion through a turbulent flow field. The rectilinear motion results are used in a quasi-steady manner to calculate the instantaneous spectrum of the rotor noise at any given rotor position; the overall spectrum is then found by averaging the instantaneous spectrum over all rotor azimuth angles. Account is taken of the fact that the rotor spends different amounts of retarded time at different rotor positions. Blade to blade correlation is included in the analysis, leading to harmonics of blade passing frequency. The spectrum of the turbulence entering the rotor is calculated by applying rapid distortion theory to an isotropic turbulence spectrum, assuming that the turbulence is stretched as it is pulled into the rotor. The inputs to the program are obtained from the atmospheric turbulence model and mean flow distortion calculation, described in another volume of this set of reports. The analytical basis is provided for a module which was incorporated in NASA's ROTONET helicopter noise prediction program. Amiet, R. K. Unspecified Center NAS1-17763; RTOP 505-63-51...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722414290
Category :
Languages : en
Pages : 36
Book Description
An analysis is presented for the calculation of noise produced by turbulent flow into a helicopter rotor. The method is based on the analysis of Amiet for the sound produced by an airfoil moving in rectilinear motion through a turbulent flow field. The rectilinear motion results are used in a quasi-steady manner to calculate the instantaneous spectrum of the rotor noise at any given rotor position; the overall spectrum is then found by averaging the instantaneous spectrum over all rotor azimuth angles. Account is taken of the fact that the rotor spends different amounts of retarded time at different rotor positions. Blade to blade correlation is included in the analysis, leading to harmonics of blade passing frequency. The spectrum of the turbulence entering the rotor is calculated by applying rapid distortion theory to an isotropic turbulence spectrum, assuming that the turbulence is stretched as it is pulled into the rotor. The inputs to the program are obtained from the atmospheric turbulence model and mean flow distortion calculation, described in another volume of this set of reports. The analytical basis is provided for a module which was incorporated in NASA's ROTONET helicopter noise prediction program. Amiet, R. K. Unspecified Center NAS1-17763; RTOP 505-63-51...
Noise Produced by Turbulent Flow Into a Rotor
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722414597
Category :
Languages : en
Pages : 38
Book Description
A users manual for a computer program for the calculation of noise produced by turbulent flow into a helicopter rotor is presented. These inputs to the program are obtained from the atmospheric turbulence model and mean flow distortion calculation, described in another volume of this set of reports. Descriptions of the various program modules and subroutines, their function, programming structure, and the required input and output variables are included. This routine is incorporated as one module of NASA's ROTONET helicopter noise prediction program. Amiet, R. K. and Egolf, C. G. and Simonich, J. C. Unspecified Center NAS1-17763; RTOP 505-63-51...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722414597
Category :
Languages : en
Pages : 38
Book Description
A users manual for a computer program for the calculation of noise produced by turbulent flow into a helicopter rotor is presented. These inputs to the program are obtained from the atmospheric turbulence model and mean flow distortion calculation, described in another volume of this set of reports. Descriptions of the various program modules and subroutines, their function, programming structure, and the required input and output variables are included. This routine is incorporated as one module of NASA's ROTONET helicopter noise prediction program. Amiet, R. K. and Egolf, C. G. and Simonich, J. C. Unspecified Center NAS1-17763; RTOP 505-63-51...
Noise Produced by Turbulent Flow Into a Rotor: Users Manual for Atmospheric Turbulence Prediction and Mean Flow and Turbulence Contraction Prediction
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 48
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 48
Book Description
Noise Produced by Turbulent Flow Into a Rotor :.
Author: John Charles Simonich
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 988
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 988
Book Description
STAR
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 904
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 904
Book Description
Aircraft Noise Prediction Program Theoretical Manual: Rotorcraft System Noise Prediction System (ROTONET), Part 4
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 282
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 282
Book Description
Computation of Rotor Noise Generation in Turbulent Flow Using Large-eddy Simulation
Author: Junye Wang
Publisher:
ISBN:
Category :
Languages : en
Pages : 107
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 107
Book Description
Experimental Assessment of Helicopter Rotor Turbulence Ingestion Noise in Hover
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 72
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 72
Book Description