Simulation of a hot coaxial jet: Direct noise prediction and flow-acoustics correlations

被引:34
作者
Bogey, Christophe [1 ]
Barre, Sebastien [1 ]
Juve, Daniel [1 ]
Bailly, Christophe [1 ]
机构
[1] Ecole Cent Lyon, CNRS, Lab Mecan Fluides & Acoust, UMR 5509, F-69134 Ecully, France
关键词
aeroacoustics; convection; flow simulation; jets; nozzles; pipe flow; vortices; LARGE-EDDY SIMULATION; DISSIPATIVE EXPLICIT SCHEMES; FAR-FIELD NOISE; SUBSONIC JET; REYNOLDS-NUMBER; COMPUTATIONAL AEROACOUSTICS; INITIAL CONDITION; SOUND GENERATION; TURBULENT JET; MIXING LAYER;
D O I
10.1063/1.3081561
中图分类号
O3 [力学];
学科分类号
08 ; 0801 ;
摘要
A coaxial jet originating from parallel coplanar pipe nozzles is computed by a compressible large eddy simulation (LES) using low-dissipation and low-dispersion schemes in order to determine its acoustic field and to study noise generation mechanisms. The jet streams are at high velocities, the primary stream is heated, and the Reynolds number based on the primary velocity and the secondary diameter is around 10(6). High levels of turbulence intensity are also specified at the nozzle exit. The jet aerodynamic field and the near-pressure field are both obtained directly from the LES. The far-field noise is calculated by solving the linear acoustic equations, from the unsteady LES data on a cylindrical surface surrounding the jet. A good agreement is observed in terms of directivity, levels, and narrow-band spectra with noise measurements carried out during the EU project CoJeN for a coaxial jet displaying same stream velocities and temperatures, coplanar nozzle outlets with identical area ratio, and a high Reynolds number. However, certainly due to differences in the properties of the nozzle-exit boundary layers with respect to the experiment, some unexpected peaks are noticed in the simulation spectra. They are attributed to the development of a Von Karman street in the inner mixing layer and to vortex pairings in the outer shear layer. High correlation levels are also calculated between the pressure waves radiated in the downstream direction and flow quantities such as axial velocity, vorticity norm, density, and temperature, taken around the end of the primary and secondary potential cores. Noise generation in the coaxial jet therefore appears significant around the end of the two potential cores. These flow regions are characterized by intermittency, a dominant Strouhal number, and variations in the convection velocity as similarly found in single jets. The use of density or temperature to compute flow-noise correlations finally seems appropriate for a heated jet flow, but might lead to correlations with acoustic disturbances in the potential core.
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页数:14
相关论文
共 60 条
[1]   CORRELATION AND PREDICTION OF JET NOISE [J].
AHUJA, KK .
JOURNAL OF SOUND AND VIBRATION, 1973, 29 (02) :155-168
[2]  
ALQADI IMA, 2003, 20033237 AIAA
[3]  
ANDERSSON N, 2005, 20052884 AIAA
[4]   The proper orthogonal decomposition of pressure fluctuations surrounding a turbulent jet [J].
Arndt, REA ;
Long, DF ;
Glauser, MN .
JOURNAL OF FLUID MECHANICS, 1997, 340 :1-33
[5]   Contributions of computational aeroacoustics to jet noise research and prediction [J].
Bailly, C ;
Bogey, C .
INTERNATIONAL JOURNAL OF COMPUTATIONAL FLUID DYNAMICS, 2004, 18 (06) :481-491
[6]   High-order, low dispersive and low dissipative explicit schemes for multiple-scale and boundary problems [J].
Berland, Julien ;
Bogey, Christophe ;
Marsden, Olivier ;
Bailly, Christophe .
JOURNAL OF COMPUTATIONAL PHYSICS, 2007, 224 (02) :637-662
[7]   Numerical study of screech generation in a planar supersonic jet [J].
Berland, Julien ;
Bogey, Christophe ;
Bailly, Christophe .
PHYSICS OF FLUIDS, 2007, 19 (07)
[8]   Current status of jet noise predictions using large-eddy simulation [J].
Bodony, Daniel J. ;
Lele, Sanjiva K. .
AIAA JOURNAL, 2008, 46 (02) :364-380
[9]   Numerical simulation of sound generated by vortex pairing in a mixing layer [J].
Bogey, C ;
Bailly, C ;
Juvé, D .
AIAA JOURNAL, 2000, 38 (12) :2210-2218
[10]   An analysis of the correlations between the turbulent flow and the sound pressure fields of subsonic jets [J].
Bogey, C. ;
Bailly, C. .
JOURNAL OF FLUID MECHANICS, 2007, 583 :71-97