有限长圆柱绕流气动噪声源特性分析
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摘要
气动噪声源的能级、分布特性及其产生根源还不够清晰。以有限长三维圆柱绕流为研究对象,基于声源方程分析气动噪声源的种类构成及其与气动参数的关系,通过数值计算得到可压非定常流场,利用气动参数定量计算圆柱顶部、中部和底部的声源大小分布,研究声源的分布特性和产生根源。结果表明,在有限长圆柱绕流场中,以偶极子声源为主,单极子声源可以忽略不计,四极子源项的值比偶极子小1～2个数量级。偶极子主要分布在来流分离点及圆柱后壁面湍流涡二次碰撞区域,四极子主要分布在来流分离点及其向后拖曳区域。偶极子声源主要由于圆柱两侧涡脱落处的脉动压力在横向(y方向)上的二阶梯度引起。以上结果为气动噪声控制的进一步研究提供了借鉴和参考。
The energy level, distribution characteristics and origin of aerodynamic noise source are not clear enough.The three-dimensional flow around a finite-length cylinder is taken as the research object. Based on acoustic source equations, the types of aerodynamic noise sources and their relationship with aerodynamic parameters are analyzed.Compressible unsteady flow is calculated numerically and then the aerodynamic parameters are used to quantitatively calculate the sound sources distribution at the top, middle and bottom of the cylinder in order to study the distribution characteristics and origin of the sound sources. Results show that the dipole sound source is dominant in the flow field and the monopole sound source is negligible, the quadrupole sound source is 1-2 orders of magnitude smaller than the dipole sound source, the dipole are mainly distributed at the separation points of incoming flow and the secondary collision zone of eddy flow on the back of cylinder, and the quadrupole is mainly distributed at the separation points of incoming flow and its drag zone. The dipole sound source is mainly caused by the two-step gradient of dynamic pressure in the transverse direction(y-direction) at both sides of the cylinder. The above conclusions can provide a theoretical basis for the aerodynamic noise control.
The energy level, distribution characteristics and origin of aerodynamic noise source are not clear enough.The three-dimensional flow around a finite-length cylinder is taken as the research object. Based on acoustic source equations, the types of aerodynamic noise sources and their relationship with aerodynamic parameters are analyzed.Compressible unsteady flow is calculated numerically and then the aerodynamic parameters are used to quantitatively calculate the sound sources distribution at the top, middle and bottom of the cylinder in order to study the distribution characteristics and origin of the sound sources. Results show that the dipole sound source is dominant in the flow field and the monopole sound source is negligible, the quadrupole sound source is 1-2 orders of magnitude smaller than the dipole sound source, the dipole are mainly distributed at the separation points of incoming flow and the secondary collision zone of eddy flow on the back of cylinder, and the quadrupole is mainly distributed at the separation points of incoming flow and its drag zone. The dipole sound source is mainly caused by the two-step gradient of dynamic pressure in the transverse direction(y-direction) at both sides of the cylinder. The above conclusions can provide a theoretical basis for the aerodynamic noise control.
引文
[1]孙晓峰,周盛.气动声学[M].北京:国防工业出版社,1994.
[2]LIGHTHILL M J.On sound generated aerodynamically.i.general theory[J].Proceedings of the Royal Society of London,1952,211(1107):564-587.
[3]LIGHTHILL M J.On sound generated aerodynamically.II.Turbulence as a source of sound[J].Proceedings of the Royal Society of London.Series A.Mathematical and Physical Sciences,1954,222(1148):1-32.
[4]CURLE N.The Influence of solid boundaries upon aerodynamic sound[C]//Proceedings of the Royal Society of London,1955,Series A(231):506-514.
[5]WILLIAMS J E F,HAWKINGS D L.Sound generation by turbulence and surfaces in arbitrary motion[J].Philosophical Transactions of the Royal Society of London.Series A,Mathematical and Physical Sciences,1969,264(1151):321-342.
[6]HOWE M S.Edge,cavity and aperture tones at very low mach numbers[J].J.Fluid.Mech,1997,330(4):61-84.
[7]HOWE M S.Acoustics of fluid-structure interactions[M].Cambridge University Press,1998.
[8]COX J S,BRENTNER K S,RUMSEY C L.Computation of vortex shedding and radiated sound for a circular cylinder:subcritical to transcritical reynolds numbers[J].Theoretical&Computational Fluid Dynamics,1998,12(4):233-253.
[9]BRENTNER K S,COX J S,RUMSEY C L,et al.Computation of sound generated by flow over a circular cylinder:an acoustic analogy approach[C]//Computational Aeroacoustics Workshop on Benchmark Problems NASA.1997:1-9.
[10]TAKAISHI T,SAGAWA A,NAGAKURA K,et al.Numerical analysis of dipole sound source around high speed trains[J].J.Acoust.Soc.Am.,2002,111(6):2601-2608.
[11]IIDA A,MIZUNO A,KATO C.Visualization of aerodynamic sound source with compact green's function[C]//Aiaa/ceas Aeroacoustics Conference&Exhibit.2002.
[12]郑朝荣,王笑寒,武岳.钝体绕流气动噪声源特性数值研究[J].哈尔滨工业大学学报,2017,49(12):146-151.ZHENG Chaorong,WANG Xiaohan,WU Yue.Numerical investigation on the characteristics of aerodynamic noise sources induced by flows around bluff bodies[J].Journal of Harbin Institute of Technology,2017,49(12):146-151.
[13][美]戈德斯坦.气动声学[M].闫再友译.北京:国防工业出版社,2014.[America]Goldstein.Aeroacoustics[M].RAN Zaiyou translate.Beijing:National Defense Industry Press,2014.
[14]唐狄毅,李文兰,乔渭阳.飞机噪声基础[M].西安:西北工业大学出版社,1995.TANG Diyi,LI Wenlan,QIAO Weiyang.Aircraft Noise[M].Xi’an:Northwestern Polytechnical University Press,1995.
[15]LEE A H,CAMPBELL R L,HAMBRIC S A.Coupled delayed-detached-eddy simulation and structural vibration of a selt-oscillating cylinder due to vortex-shedding[J].Journal of Fluids and Structural,2014,48(7):216-234.
[16]蔡建程,潘杰,鄂世举,等.圆柱绕流气动声的偶极子及四极子源法定量研究[J].声学学报,2016,41(3):420-427.CAI Jiancheng,PAN Jie,E Shiju,et al.Quantitive study of the aerodynamic sound induced by the flow past a cylinder based on dipole and quadrupole m odels[J].Acta Acustica,2016,41(3):420-427.
[2]LIGHTHILL M J.On sound generated aerodynamically.i.general theory[J].Proceedings of the Royal Society of London,1952,211(1107):564-587.
[3]LIGHTHILL M J.On sound generated aerodynamically.II.Turbulence as a source of sound[J].Proceedings of the Royal Society of London.Series A.Mathematical and Physical Sciences,1954,222(1148):1-32.
[4]CURLE N.The Influence of solid boundaries upon aerodynamic sound[C]//Proceedings of the Royal Society of London,1955,Series A(231):506-514.
[5]WILLIAMS J E F,HAWKINGS D L.Sound generation by turbulence and surfaces in arbitrary motion[J].Philosophical Transactions of the Royal Society of London.Series A,Mathematical and Physical Sciences,1969,264(1151):321-342.
[6]HOWE M S.Edge,cavity and aperture tones at very low mach numbers[J].J.Fluid.Mech,1997,330(4):61-84.
[7]HOWE M S.Acoustics of fluid-structure interactions[M].Cambridge University Press,1998.
[8]COX J S,BRENTNER K S,RUMSEY C L.Computation of vortex shedding and radiated sound for a circular cylinder:subcritical to transcritical reynolds numbers[J].Theoretical&Computational Fluid Dynamics,1998,12(4):233-253.
[9]BRENTNER K S,COX J S,RUMSEY C L,et al.Computation of sound generated by flow over a circular cylinder:an acoustic analogy approach[C]//Computational Aeroacoustics Workshop on Benchmark Problems NASA.1997:1-9.
[10]TAKAISHI T,SAGAWA A,NAGAKURA K,et al.Numerical analysis of dipole sound source around high speed trains[J].J.Acoust.Soc.Am.,2002,111(6):2601-2608.
[11]IIDA A,MIZUNO A,KATO C.Visualization of aerodynamic sound source with compact green's function[C]//Aiaa/ceas Aeroacoustics Conference&Exhibit.2002.
[12]郑朝荣,王笑寒,武岳.钝体绕流气动噪声源特性数值研究[J].哈尔滨工业大学学报,2017,49(12):146-151.ZHENG Chaorong,WANG Xiaohan,WU Yue.Numerical investigation on the characteristics of aerodynamic noise sources induced by flows around bluff bodies[J].Journal of Harbin Institute of Technology,2017,49(12):146-151.
[13][美]戈德斯坦.气动声学[M].闫再友译.北京:国防工业出版社,2014.[America]Goldstein.Aeroacoustics[M].RAN Zaiyou translate.Beijing:National Defense Industry Press,2014.
[14]唐狄毅,李文兰,乔渭阳.飞机噪声基础[M].西安:西北工业大学出版社,1995.TANG Diyi,LI Wenlan,QIAO Weiyang.Aircraft Noise[M].Xi’an:Northwestern Polytechnical University Press,1995.
[15]LEE A H,CAMPBELL R L,HAMBRIC S A.Coupled delayed-detached-eddy simulation and structural vibration of a selt-oscillating cylinder due to vortex-shedding[J].Journal of Fluids and Structural,2014,48(7):216-234.
[16]蔡建程,潘杰,鄂世举,等.圆柱绕流气动声的偶极子及四极子源法定量研究[J].声学学报,2016,41(3):420-427.CAI Jiancheng,PAN Jie,E Shiju,et al.Quantitive study of the aerodynamic sound induced by the flow past a cylinder based on dipole and quadrupole m odels[J].Acta Acustica,2016,41(3):420-427.