直升机旋翼桨—涡干扰气动噪声的研究
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摘要
旋翼桨-涡干扰噪声问题是直升机气动声学领域的一个研究热点和难点。本文应用自由尾迹涡流理论和气动声学时域方法对旋翼桨-涡干扰气动噪声进行了理论分析研究，并在航空声学实验室和外场进行了模拟旋翼桨-涡干扰噪声的实验研究。主要工作包括：
作为前提和背景，本文首先简要介绍了直升机旋翼噪声的分类，指出了旋翼桨-涡干扰噪声研究的重点和难点。
在第二章，使用Beddoes预定尾迹模型，建立了一个用于旋翼桨-涡干扰特性机理分析的简化数学模型，分别对旋翼桨-涡干扰位置、桨-涡干扰距离和声辐射方向性等进行了计算和分析，得出了有意义的结果。
基于桨叶二阶升力线理论和旋翼自由尾迹模型，本文在第三章建立了一个适合于直升机旋翼尾迹结构及桨-涡干扰气动特性分析的方法和模型。
在第四章，基于上述旋翼自由尾迹方法，并使用Farassat 1A声学时域公式，建立了适合于直升机悬停和前飞时旋翼桨-涡干扰噪声计算的模型。
应用该模型，分别以UH-1模型旋翼、本文试验的模型旋翼以及Z-8直升机旋翼为算例，对不同飞行条件下的旋翼气动噪声进行了计算，验证了本文的计算方法。
在第六章，基于桨-涡靠近通过是非共面剪刀式布置旋翼流场的一个重要特征，提出了使用剪刀式布置旋翼来模拟旋翼桨-涡干扰噪声实验的新构想，并设计了用于噪声实验的模型。
本文第七章分别在“消声室”和外场进行了模型旋翼的桨-涡干扰噪声实验，对不同马赫数、不同桨距角以及不同旋翼布置情况下的不同测点进行了噪声测量，得出了一些新的结论。
The research on the rotor blade-vortex interaction (BVI) noise is a very important aspect and a very challenging subject in the rotorcraft aeroacoustics field. In this thesis, both the analytical investigation, based upon the rotor free-wake vortex theory and the aeroacoustic methodology in time domain, and the experimental investigation, simulated in an aeroacoustic laboratory and at outdoors, on the BVI noise have been performed. The major contributions of the author's research work are as follows:
As the background of the work, the classification of helicopter rotor noise sources is introduced briefly, and the important and difficult aspects in the BVI noise research are pointed out.
In Chapter 2, a simplified analytical model is presented for the analysis of the BVI mechanism, adopting the Beddoes' prescribed wake model. By this model, the azimuthal location and miss-distance of the BVI and the radiation directivity of the BVI noise are calculated and discussed, and some conclusions are obtained.
In Chapter 3, based upon the blade second-order lifting-line model and rotor free-wake model, an analytical method is developed for predicting the rotor wake structure and BVI airload.
Based upon the rotor free-wake analysis and the Farassat Formulation 1A in time domain, an analytical model, which can be used to predict the BVI noise in hover and in forward flight, has been developed in Chapter 4.
In Chapter 5, the UH-1 model rotor, the model rotor measured in the present work and the helicopter Z-8 rotor are taken as numerical examples, the calculations on rotor noise under different flight conditions are carried out for validation purposes.
In Chapter 6, a new idea for simulating rotor BVI noise experiment is presented using a scissors rotor configuration with the vertical separation between a pair of rotors, based upon the fact that the important aerodynamic feature of this scissors rotor configuration is its close blade-vortex encounter. And the models and facilities designed for the BVI noise experiment are given.
Finally, the experiments on the rotor BVI noise are conducted both in an aeroacoustic laboratory and at outdoors, and the noise characteristics at different locations are measured on different blade-tip Mach numbers, collective pitch angles and rotor configurations. Based on the experimental results, some new conclusions are presented.
作为前提和背景，本文首先简要介绍了直升机旋翼噪声的分类，指出了旋翼桨-涡干扰噪声研究的重点和难点。
在第二章，使用Beddoes预定尾迹模型，建立了一个用于旋翼桨-涡干扰特性机理分析的简化数学模型，分别对旋翼桨-涡干扰位置、桨-涡干扰距离和声辐射方向性等进行了计算和分析，得出了有意义的结果。
基于桨叶二阶升力线理论和旋翼自由尾迹模型，本文在第三章建立了一个适合于直升机旋翼尾迹结构及桨-涡干扰气动特性分析的方法和模型。
在第四章，基于上述旋翼自由尾迹方法，并使用Farassat 1A声学时域公式，建立了适合于直升机悬停和前飞时旋翼桨-涡干扰噪声计算的模型。
应用该模型，分别以UH-1模型旋翼、本文试验的模型旋翼以及Z-8直升机旋翼为算例，对不同飞行条件下的旋翼气动噪声进行了计算，验证了本文的计算方法。
在第六章，基于桨-涡靠近通过是非共面剪刀式布置旋翼流场的一个重要特征，提出了使用剪刀式布置旋翼来模拟旋翼桨-涡干扰噪声实验的新构想，并设计了用于噪声实验的模型。
本文第七章分别在“消声室”和外场进行了模型旋翼的桨-涡干扰噪声实验，对不同马赫数、不同桨距角以及不同旋翼布置情况下的不同测点进行了噪声测量，得出了一些新的结论。
The research on the rotor blade-vortex interaction (BVI) noise is a very important aspect and a very challenging subject in the rotorcraft aeroacoustics field. In this thesis, both the analytical investigation, based upon the rotor free-wake vortex theory and the aeroacoustic methodology in time domain, and the experimental investigation, simulated in an aeroacoustic laboratory and at outdoors, on the BVI noise have been performed. The major contributions of the author's research work are as follows:
As the background of the work, the classification of helicopter rotor noise sources is introduced briefly, and the important and difficult aspects in the BVI noise research are pointed out.
In Chapter 2, a simplified analytical model is presented for the analysis of the BVI mechanism, adopting the Beddoes' prescribed wake model. By this model, the azimuthal location and miss-distance of the BVI and the radiation directivity of the BVI noise are calculated and discussed, and some conclusions are obtained.
In Chapter 3, based upon the blade second-order lifting-line model and rotor free-wake model, an analytical method is developed for predicting the rotor wake structure and BVI airload.
Based upon the rotor free-wake analysis and the Farassat Formulation 1A in time domain, an analytical model, which can be used to predict the BVI noise in hover and in forward flight, has been developed in Chapter 4.
In Chapter 5, the UH-1 model rotor, the model rotor measured in the present work and the helicopter Z-8 rotor are taken as numerical examples, the calculations on rotor noise under different flight conditions are carried out for validation purposes.
In Chapter 6, a new idea for simulating rotor BVI noise experiment is presented using a scissors rotor configuration with the vertical separation between a pair of rotors, based upon the fact that the important aerodynamic feature of this scissors rotor configuration is its close blade-vortex encounter. And the models and facilities designed for the BVI noise experiment are given.
Finally, the experiments on the rotor BVI noise are conducted both in an aeroacoustic laboratory and at outdoors, and the noise characteristics at different locations are measured on different blade-tip Mach numbers, collective pitch angles and rotor configurations. Based on the experimental results, some new conclusions are presented.
引文
[1] F. Caradonna, C. Kitapliogiu, Method for the Prediction of Blade-Vortex Interaction Noise, Presented at the American Helicopter Society Technical Specialists' Meeting for Rotorcraft Acoustics and Aerodynamics, Oct. 1997
[2] B. W.-C. Sim, A. R. George, Development of a Rotor Aerodynamic Load Prediction Scheme for Blade-Vortex Interaction Noise Study, Presented at the American Helicopter Society 51 st Annual National Forum, May 1995
[3] J. D. Baeder, and G. R. Srinivasan, Computational Aeroacoustic Study of Isolated Blade-Vortex Interaction Noise, American Helicopter Society Aeromechanics Specialists Conference, January 1994
[4] H. Khanna, J. D. Baeder, Coupled Wake/CFD Solutions for Rotors in Hover, Presented at American Helicopter Society 52nd Annual Forum Proceedings, Washington, D.C., June 1996.
[5] G. R. Srinivasan, A Free-Wake Euler and Navier-Stokes CFD Method and Its Application to Helicopter Rotors Including Dynamic Stall, JAI Associates Inc., TR 93-01, 1993
[6] J. O. Bridgeman, K. Ramachandran, et al, A Computational Analysis of Parallel Blade-Vortex Interactions Using Vorticity Embedding, Presented at American Helicopter Society 50th Annual Forum Proceedings, Washington, D.C., May 1994
[7] G.R. Srinivasan, J.D. Baeder, TURNS: A Free-Wade Euler/Navier-Stokes Numerical Method for Helicopter Rotors, AIAA Journal, Vol.31, No.5, May 1993
[8] W. Johnson, Helicopter Theory, Princeton University Press, 1980
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[12] S. Devon Prichard, L. Casey, Burley Computational Techniques for Improved Blade Vortex Interaction Modeling Presented at the American Helicopter Society 51st Annual Forum, Fort Worth, TX, June 1995
[13] G.. Rahier, Y. Delrieux, Influence of Vortex Models on Blade-Vortex Interaction Load and Noise Predictions, Presented at the AHS Technical Specialists' Meeting for Rotor Acoustic&Aerodynamics, Williamburg, Oct 1997
[14] F. H. Schmitz, G. Gopalan and B.-C. Sim, Flight Trajectory Management to Reduce
Helicopter Blade-Vortex Interaction(BVI) Noise with Head/Tailwind Effects, Presented at the 26th European Rotorcraft Forum, Sep. 2000
[15] B. C. Kuo, B. W. Sire and F. H. Schrnity, Blade-Vortex Interaction Wave Radiation Patterns of Helicopter Blades With Different Leading-Edge Geometry, Presented at the American Helicopter Society 58th Annual Forum, 2002
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[18] Y. H. Yu, S. Lee, Rotor High-Speed Noise Prediction with a Combined CFD-Kirchhoff Method, Presented at the 50th AHS Forum, May 1994
[19] 宋文萍，韩忠华，杨爱明，乔志德，旋翼跨声速流动气动噪声的一种高效算法，西北工业大学学报，Vol．19，No．4，2001
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[22] S. Woo, K.-W. Oh, Two-Dimensional BVI Revisited Using Unstructured Dynamic Meshes, Presented at the American Helicopter Society 58th Annual Forum, June 2002
[23] K. S. Brentner, Prediction of Helicopter Rotor Discrete Frequency Noise, NASA TM 87721, Oct. 1996
[24] F. X. Caradonna, R. C. Strawn and J. O. Bridge, An Experimental and Computational Study of Rotor-Vortex Interactions, Presented at the 14th European Rotorcraft Forum, MiLano, Sept 1988
[25] B. Malovrh, F. Gandhi and L. Tauszig, Sensitivity of Helicopter BVI-Indueed Noise and Vibration to Variations in Individual Interaction-Parameter, Presented at the American Helicopter Society 57th Annual Forum, Washington, DC. May 2001
[26] E H. Schmitz, et al, A Note on the General Scaling of Helicopter Blade-Vortex Interaction Noise, Presented at the 38th Annual National Forum of American Helicopter Society, Anaheim, CA, 1982
[27] 韩忠华，王立群，杨爱明，乔志德，旋翼桨尖几何形状对旋翼气动噪声影响的定量计算分析，计算物理，Vol．18，No．6，2001
[28] 徐国华，高正，悬停状态下模型旋翼噪声试验的初步研究，空气动力学报，Vol．14，No．1，1996
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[31] 尹坚平，胡章伟，由计算的三元非定常压力数据来预估旋翼辐射的桨．涡干扰噪声航空学报，Vol．17，No．6，1996
[32] 乔渭阳，唐狄毅，李文兰，旋翼BVI噪声的理论模拟与分析，航空学报，Vol．15，No．6，1994
[33] 张强，王华明，胡章伟，直升机噪声信号的小波分析，声学学报，Vol．26，No．5，2001
[34] T. S. Beddoes, A Wake Model for High Resolution Airloads, Presented at AHS Conference, 1985
[35] B. W.-C. Sim, F. H. Schmitz, Blade-vortex Interaction(BVI) Noise: Retreating side Characteristics, Sensitivity to Chordwise Loading and Unsteady Loading and Unsteady Aerodynamics, American Helicopter Society Aeromechanics Specialists Meeting, 2000.
[36] A. F Landgrebe, and E.D. Bellinger, An Investigation of the Quantitative Applicability of Model Helicopter Rotor Wake Patterns Obtained From a Water Tunnel, USAAMRDL TR 71-69, 1991
[37] M. V. Lowson, Focusing of Helicopter BVI Noise, Journal of Sound and Vibration, Vol.190, No.3, 1996
[38] B. W.-C. Sim, F. H. Schmitz, Acoustic Phasing and Amplification Effects of Single-Rotor Helicopter Blade-Vortex Interactions, American Helicopter Society 55th Annual Forum, 1998
[39] F. H. Schmitz, B. W.-C.Sim, Radiation and Directionality Characteristics of Advancing Side Blade-Vortex Interaction (BVI) Noise, 6th AIAA/CEAS Aeroacoustic Conference, June, 2000
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[59] 俞元亮，胡章伟，陈玉清，谷嘉锦，航空声学，航空专业教材编审组，1986．7
[2] B. W.-C. Sim, A. R. George, Development of a Rotor Aerodynamic Load Prediction Scheme for Blade-Vortex Interaction Noise Study, Presented at the American Helicopter Society 51 st Annual National Forum, May 1995
[3] J. D. Baeder, and G. R. Srinivasan, Computational Aeroacoustic Study of Isolated Blade-Vortex Interaction Noise, American Helicopter Society Aeromechanics Specialists Conference, January 1994
[4] H. Khanna, J. D. Baeder, Coupled Wake/CFD Solutions for Rotors in Hover, Presented at American Helicopter Society 52nd Annual Forum Proceedings, Washington, D.C., June 1996.
[5] G. R. Srinivasan, A Free-Wake Euler and Navier-Stokes CFD Method and Its Application to Helicopter Rotors Including Dynamic Stall, JAI Associates Inc., TR 93-01, 1993
[6] J. O. Bridgeman, K. Ramachandran, et al, A Computational Analysis of Parallel Blade-Vortex Interactions Using Vorticity Embedding, Presented at American Helicopter Society 50th Annual Forum Proceedings, Washington, D.C., May 1994
[7] G.R. Srinivasan, J.D. Baeder, TURNS: A Free-Wade Euler/Navier-Stokes Numerical Method for Helicopter Rotors, AIAA Journal, Vol.31, No.5, May 1993
[8] W. Johnson, Helicopter Theory, Princeton University Press, 1980
[9] 徐国华，高正，国外直升机旋翼噪声研究，第五届全国直升机年会学术论文集，上海，1988
[10] 徐国华，高正，美国直升机旋翼噪声预估系统的现状和发展趋势，南京航空学院学报，Vol．25，No．1，1993
[11] 徐国华，直升机旋翼噪声分析及估算方法，硕士论文，南京航空学院，1990．2
[12] S. Devon Prichard, L. Casey, Burley Computational Techniques for Improved Blade Vortex Interaction Modeling Presented at the American Helicopter Society 51st Annual Forum, Fort Worth, TX, June 1995
[13] G.. Rahier, Y. Delrieux, Influence of Vortex Models on Blade-Vortex Interaction Load and Noise Predictions, Presented at the AHS Technical Specialists' Meeting for Rotor Acoustic&Aerodynamics, Williamburg, Oct 1997
[14] F. H. Schmitz, G. Gopalan and B.-C. Sim, Flight Trajectory Management to Reduce
Helicopter Blade-Vortex Interaction(BVI) Noise with Head/Tailwind Effects, Presented at the 26th European Rotorcraft Forum, Sep. 2000
[15] B. C. Kuo, B. W. Sire and F. H. Schrnity, Blade-Vortex Interaction Wave Radiation Patterns of Helicopter Blades With Different Leading-Edge Geometry, Presented at the American Helicopter Society 58th Annual Forum, 2002
[16] K. R. Shenoy, A. Semiemperical, High-Speed Rotor Noise Prediction Technique, Presented at 38th Annual Forum of the American Helicopter Society, May 1982
[17] O. Rho, Y. S. Kim, An Analysis on High Speed Impulsive Noise of Transonic Helicopter Rotor, Presented at the AHS 48th Annual Forum, June 1992
[18] Y. H. Yu, S. Lee, Rotor High-Speed Noise Prediction with a Combined CFD-Kirchhoff Method, Presented at the 50th AHS Forum, May 1994
[19] 宋文萍，韩忠华，杨爱明，乔志德，旋翼跨声速流动气动噪声的一种高效算法，西北工业大学学报，Vol．19，No．4，2001
[20] S. Lewy, M. Caplot, Review of Some Theoretical and Experiment Studies on Helicopter Rotor Noise, Vertica, Vol. 18, No.4, 1995
[21] B. Munsky, E Gandhi and L. Yauszig, An Analysis of Helicopter Blade-Vortex Interaction Noise with Flight Path or Attitude Modification, Presented at the American Helicopter Society 58th Annual Forum, June 2002
[22] S. Woo, K.-W. Oh, Two-Dimensional BVI Revisited Using Unstructured Dynamic Meshes, Presented at the American Helicopter Society 58th Annual Forum, June 2002
[23] K. S. Brentner, Prediction of Helicopter Rotor Discrete Frequency Noise, NASA TM 87721, Oct. 1996
[24] F. X. Caradonna, R. C. Strawn and J. O. Bridge, An Experimental and Computational Study of Rotor-Vortex Interactions, Presented at the 14th European Rotorcraft Forum, MiLano, Sept 1988
[25] B. Malovrh, F. Gandhi and L. Tauszig, Sensitivity of Helicopter BVI-Indueed Noise and Vibration to Variations in Individual Interaction-Parameter, Presented at the American Helicopter Society 57th Annual Forum, Washington, DC. May 2001
[26] E H. Schmitz, et al, A Note on the General Scaling of Helicopter Blade-Vortex Interaction Noise, Presented at the 38th Annual National Forum of American Helicopter Society, Anaheim, CA, 1982
[27] 韩忠华，王立群，杨爱明，乔志德，旋翼桨尖几何形状对旋翼气动噪声影响的定量计算分析，计算物理，Vol．18，No．6，2001
[28] 徐国华，高正，悬停状态下模型旋翼噪声试验的初步研究，空气动力学报，Vol．14，No．1，1996
[29] 徐国华，高正，直升机旋翼旋转噪声的估算，南京航空学院学报，1991．6，Vol．23，NO．2
[30] 陈本现，王华明，悬停状态下的旋翼旋转噪声分析，第十八届全国直升机年会，2002，pp510～515
[31] 尹坚平，胡章伟，由计算的三元非定常压力数据来预估旋翼辐射的桨．涡干扰噪声航空学报，Vol．17，No．6，1996
[32] 乔渭阳，唐狄毅，李文兰，旋翼BVI噪声的理论模拟与分析，航空学报，Vol．15，No．6，1994
[33] 张强，王华明，胡章伟，直升机噪声信号的小波分析，声学学报，Vol．26，No．5，2001
[34] T. S. Beddoes, A Wake Model for High Resolution Airloads, Presented at AHS Conference, 1985
[35] B. W.-C. Sim, F. H. Schmitz, Blade-vortex Interaction(BVI) Noise: Retreating side Characteristics, Sensitivity to Chordwise Loading and Unsteady Loading and Unsteady Aerodynamics, American Helicopter Society Aeromechanics Specialists Meeting, 2000.
[36] A. F Landgrebe, and E.D. Bellinger, An Investigation of the Quantitative Applicability of Model Helicopter Rotor Wake Patterns Obtained From a Water Tunnel, USAAMRDL TR 71-69, 1991
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