Aagaard Madsen , Helge

Bertagnolio, Franck

Fischer, Andreas

Online Research Database In Technology

                       General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.  • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal   If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.     Downloaded from orbit.dtu.dk on: Dec 20, 2017Measurement of high frequency surface pressure fluctuations for blade noisecharacterizationAagaard Madsen , Helge; Bertagnolio, Franck; Fischer, AndreasPublication date:2012Link back to DTU OrbitCitation (APA):Aagaard Madsen , H., Bertagnolio, F., & Fischer, A. (2012). Measurement of high frequency surface pressurefluctuations for blade noise characterization [Sound/Visual production (digital)]. IQPC Conference on WindTurbine Noise and Vibration Control, Bremen, Germany, 22/10/2012Measurement of high frequency surface pressure fluctuations for blade noise characterization Helge Aagaard Madsen Franck Bertagnolio Andreas Fischer   Section Aeroelastic Design Department of Wind Energy  hama@dtu.dk  DTU Wind Energy, Technical University of Denmark Outline HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012   Why using high frequency surface pressure  measurements ?    Surface pressure to far field noise    Measurement technique     Wind tunnel measurements compared with  model results    Measurements on a full scale 80m diameter  rotor    Influence of different inflow conditions on the  noise source    Perspectives for application of the technique DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Why using high frequency  surface pressure (SP) measurements for aeroacoustic  characterization ?   DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012   SP is the source of trailing edge (TE) noise      SP is the source of turbulent inflow (TI) noise    SP has a high intensity compared with  ambient   noise    DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012     Measuring SP enables correlation with detailed  inflow  data from inflow sensors on the blade    Measuring SP provides more accurate aeroacoustic  characterization during design and testing of new low  noise airfoil designs     Measuring SP provides detailed noise source  information, enabling continuous, optimal input to  the turbine control system for operation  within noise constrains DTU Wind Energy, Technical University of Denmark SP in a turbulent boundary layer has a high intensity compared with ambient noise  Laminar bl HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Transition Turbulent PSD uncali-brated DTU Wind Energy, Technical University of Denmark SP in the turbulent boundary layer has a high intensity compared with the farfield sound  HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Based on set-up in the Virginia-Tech Wind Tunnel 2011 – NACA64-618 airfoil at 1.5 mill Re DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 The inflow to the blade is varying considerably in time, in particular over 1p -the same is the noise source Measured inflow angle at radius 30m on a 2MW turbine DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Drawbacks with the SP technique compared with traditional far field measurements   it is measurements at a  cross section of a blade    uncertainty in converting the  SP to the far field noise    …….    DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Surface pressure to far field noise   DTU Wind Energy, Technical University of Denmark TE Noise Mechanism          Using TNO model & CFD to evaluate:  HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 2y3y1y1 2( )U y( , )P k1 2 3, ,u u uFar field sound by scattering ( )PS Turbulent boundary layer Surface pressure fluctuations )},,{( 31 kkP kDTU Wind Energy, Technical University of Denmark TNO model* + CFD RANS Calculation …yield SP spectrum (Blake, 1986): HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012   222 21 10 2 2 2 22 1 22 2 01 3 2( , ) 4 ( ) ( , ) e dkym ck UP L y u U k yk k y           k k  232 519.0745.0TkL  Tku  45.022Isotropic turbulence In-house CFD RANS code EllipSys2D Empirical approx. Von Karman Isotropic Spectrum 23519.0 TkF. Bertagnolio, Experimental Investigation and Calibration of Surface Pressure Modeling for Trailing Edge Noise, in: Proc. of Inter-Noise 2011 Conf., Osaka, Japan. * modified TNO model: DTU Wind Energy, Technical University of Denmark TE Noise Evaluation from SP Spectra •Far-Field Noise (Howe, 1978):     •Surface Pressure Frequency-Spectrum:  HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012   3131 dd),,()(      kkkkPP  131102d),0,(4)(         kkkPkcRLSspanP Measured by HF mics. DTU Wind Energy, Technical University of Denmark Turbulent Inflow Noise   Idealized Airfoil as an Half-Plane     2y3y1yFar field sound Turbulent Inflow P2gustuU1 HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Turbulent Inflow Noise Model       Amiet’s Theory (1976)  Linearized Inviscid Theory for flat plate with 0-mean loading  •  Inflow turbulence as a harmonic turbulent gust      •  Surface pressure response using Sears’ theory:           where g is the transfer response function  1 3 3i( )1 3 1 3 0 0 1 1 3( , , , , ) 2 ( , , ) ek Ut k xP x x t k k v g x k k   1 1 3 3i( ( - ) )2,gust 0 ek x Ut k xu v 1x2x2gustu3xPU1 HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Turbulent Inflow Noise Model         The energy spectrum of the local airfoil surface  pressure jump fluctuations then reads:            Pressure jump fluctuations will radiate as dipole      Far Field Noise   Energy spectrum of u2gust 1x2x3x2gustu PU1           33122313102,,,,,2, dkkKkKgkKgUxp        3122231220,,,, KKKKrLdUcybrS  Pressure jump fluctuations radiate as dipole to far field noise   HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 The measurement technique   DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 The measurement technique     Flush-mounted HF microphones      HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Calibration of microphones in cooperation with B&K HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Wind tunnel measurements compared with model results DTU Wind Energy, Technical University of Denmark Test in the LM Wind Tunnel - 2007         Aerodynamic Test Facility                NACA0015 Airfoil Section                         Surface Pressure Measurement Holes   HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Surf. Pres. Measurements near TE HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Virginia Tech measurements 2011* - NACA64-618 airfoil with microphones HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 * PhD thesis report by Andreas Fischer (2011)  “Experimental characterization of airfoil boundary layers for improvement of aeroacoustic and aerodynamic modeling ” Can we transfer SP to far field sound ? DTU Wind Energy, Technical University of Denmark Virginia Tech measurements 2011* - NACA64-618 airfoil with microphones HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 * PhD thesis report by Andreas Fischer (2011)  “Experimental characterization of airfoil boundary layers for improvement of aeroacoustic and aerodynamic modeling ” Derived from SP measurements DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Measurements on a full scale 80m diameter rotor - From the DAN-AERO project -   DTU Wind Energy, Technical University of Denmark Measurement of SP on a full scale rotor blade, 80m diameter rotor, 2MW - - DAN-AERO MW project  surface pressure and inflow measured at 4 radial stations  the outboard station also instrumented with around 60 microphones for high frequency surface pressure measurements  high frequency measurements of the inflow  measurements from June to September 2009 HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Installation of the 38.8m instrumented blade in May 2009 HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark Campaign measurements  from June to September 2009 HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Microphone holes Pressure  holes DTU Wind Energy, Technical University of Denmark Measurement of SP on a full scale rotor blade, 80m diameter rotor, 2MW HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 TE spectra measured during free inflow  at 9-11m/s Each spectrum is based on 0.5sec DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 TE + LE spectra measured during free inflow  at 9-11m/s Each spectrum is based on 0.5sec DTU Wind Energy, Technical University of Denmark Influence of different inflow conditions on the  noise source HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Influence of turbulence in inflow ?   turbulence grid in wind  tunnel    increased turbulent  inflow to rotor due to  wake operation  DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Influence of turbulence in inflow ? DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Deviations due to influence of turbulence in inflow ? DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Influence of wake operation - distance to upstream turbine 3.5D DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Influence of wake operation - distance to upstream turbine 3.5D Increased turbulence level increases AOA variations DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Influence of wake operation - distance to upstream turbine 3.5D DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Influence of wake operation - distance to upstream turbine 3.5D Trailing edge Leading edge DTU Wind Energy, Technical University of Denmark Perspectives for application  of the technique HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 DTU Wind Energy, Technical University of Denmark A blade mounted sensor system for aeroacoustic noise source monitoring and control HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Objectives of blade mounted monitoring system:    continuous monitoring of the noise source by measuring  HF SP at a few points on each blade    derive total noise of turbine based on numerical modelling and experimental calibration    derive details of noise source variation as function of blade position    Advantages of system    Detailed and continuous source monitoring enables  changes of turbine control system only when necessary    Detailed source monitoring can provide input to the  control system on an azimuth level, e.g. for individual  pitch control to reduce/avoid amplitude noise  modulation DTU Wind Energy, Technical University of Denmark Proposed system HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Data processing and analysis system Surface mounted microphones from B&K DTU Wind Energy, Technical University of Denmark Example of measured spectra on the 2MW rotor HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 One output screen from the system could be continuously updated PSD spectra of surface pressure fluctuations DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Thank you for  your attention The work has been carried out within the projects DAN-AERO and DAN-AERO II  Funded partly by EUDP; contracts ENS-33033-0074  and ENS-64009-0258   Partly by the project participants:  - Siemens - Vestas - LM Wind Power - Dong Energy - DTU Wind Energy Acknowledgements DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Thank you for  your attention DTU Wind Energy, Technical University of Denmark HAa Madsen -- Presentation at IQPC "Wind Turbine Noise and Vibration Control", 22-24 October 2012 Comparison of SP measured in wind tunnel and on the NM80 2MW rotor - preliminary c=0.9m – wind tunnel airfoil model c=1.2m - rotor difference in Re number same Re number 

Measurement of high frequency surface pressure fluctuations for blade noise characterization

http://orbit.dtu.dk/ws/files/51513848/IQPC_Bremen_Oktober_2012.pdf

Measurement of high frequency surface pressure fluctuations for blade noise characterization

Abstract

Similar works

Full text

Available Versions

Online Research Database In Technology