A hybrid computational fluid dynamics (CFD) and computational aeroacoustics (CAA) method is used to compute the acoustic field of turbulent hot jets at a Reynolds number and a Mach number . The flow field computations are performed by highly resolved large-eddy simulations (LES), from which sound source terms are extracted to compute the acoustic field by solving the acoustic perturbation equations (APE). Two jets are considered to analyze the impact of exit conditions on the resulting jet sound field. First, a jet emanating from a fully resolved non-generic nozzle is simulated by solving the discrete conservation equations. This computation of the jet flow is denoted free-exit-flow (FEF) formulation. For the second computation, the nozzle geometry is not included in the computational domain. Time averaged exit conditions, i.e. velocity and density profiles of the first formulation, plus a jet forcing in form of vortex rings are imposed at the inlet of the second jet configuration. This formulation is denoted imposed-exit-flow (IEF) formulation. The free-exit-flow case shows up to 50% higher turbulent kinetic energy than the imposed-exit-flow case in the jet near field, which drastically impacts noise generation. The FEF and IEF configurations reveal quite a different qualitative behavior of the sound spectra, especially in the sideline direction where the entropy source term dominates sound generation. This difference occurs since the noise sources generated by density and pressure fluctuations are not perfectly modeled by the vortex ring forcing method in the IEF solution. However, the total overall sound pressure level shows the same qualitative behavior for the FEF and IEF formulations. Towards the downstream direction, the sound spectra of the FEF and IEF solutions converge.
Accepted:
Published online:
Mehmet Onur Cetin 1; Seong Ryong Koh 1; Matthias Meinke 1, 2; Wolfgang Schröder 1, 2
@article{CRMECA_2018__346_10_932_0, author = {Mehmet Onur Cetin and Seong Ryong Koh and Matthias Meinke and Wolfgang Schr\"oder}, title = {Computational analysis of exit conditions on the sound field of turbulent hot jets}, journal = {Comptes Rendus. M\'ecanique}, pages = {932--947}, publisher = {Elsevier}, volume = {346}, number = {10}, year = {2018}, doi = {10.1016/j.crme.2018.07.006}, language = {en}, }
TY - JOUR AU - Mehmet Onur Cetin AU - Seong Ryong Koh AU - Matthias Meinke AU - Wolfgang Schröder TI - Computational analysis of exit conditions on the sound field of turbulent hot jets JO - Comptes Rendus. Mécanique PY - 2018 SP - 932 EP - 947 VL - 346 IS - 10 PB - Elsevier DO - 10.1016/j.crme.2018.07.006 LA - en ID - CRMECA_2018__346_10_932_0 ER -
%0 Journal Article %A Mehmet Onur Cetin %A Seong Ryong Koh %A Matthias Meinke %A Wolfgang Schröder %T Computational analysis of exit conditions on the sound field of turbulent hot jets %J Comptes Rendus. Mécanique %D 2018 %P 932-947 %V 346 %N 10 %I Elsevier %R 10.1016/j.crme.2018.07.006 %G en %F CRMECA_2018__346_10_932_0
Mehmet Onur Cetin; Seong Ryong Koh; Matthias Meinke; Wolfgang Schröder. Computational analysis of exit conditions on the sound field of turbulent hot jets. Comptes Rendus. Mécanique, Volume 346 (2018) no. 10, pp. 932-947. doi : 10.1016/j.crme.2018.07.006. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2018.07.006/
[1] Effect of Nozzle Exit Conditions on Subsonic Jet Noise, 2011 (AIAA Paper, 2011–2704)
[2] Effects of Inflow Conditions and Subgrid Model on LES for Turbulent Jets, 2005 (AIAA Paper, 2005–2925)
[3] Numerical study of eigenmode forcing effects on jet flow development and noise generation mechanisms, Phys. Fluids, Volume 21 (2009) no. 4
[4] Influence of nozzle-exit boundary-layer conditions on the flow and acoustic fields of initially laminar jets, J. Fluid Mech., Volume 663 (2010), pp. 507-538
[5] Identification of the effects of the nozzle-exit boundary-layer thickness and its corresponding Reynolds number in initially highly disturbed subsonic jets, Phys. Fluids, Volume 25 (2013) no. 5
[6] Current status of jet noise predictions using large-eddy simulation, AIAA J., Volume 46 (2008) no. 2, pp. 364-380
[7] On using large-eddy simulation for the prediction of noise from cold and heated turbulent jets, Phys. Fluids, Volume 17 (2005) no. 8
[8] Noise prediction for increasingly complex jets. Part II: applications, Int. J. Aeroacoust., Volume 4 (2005) no. 3, pp. 247-266
[9] Turbulence and heat excited noise sources in single and coaxial jets, J. Sound Vib., Volume 329 (2010) no. 7, pp. 786-803
[10] Aeroacoustics of hot jets, J. Fluid Mech., Volume 516 (2004), pp. 39-82
[11] Transition to turbulence and noise radiation in heated coaxial jet flows, Phys. Fluids, Volume 28 (2016) no. 4
[12] Effect of Heating on Turbulent Density Fluctuations and Noise Generation from High Speed Jets, 2004 (AIAA Paper, 2004–3016)
[13] Computational analyses of offset-stream nozzles for noise reduction, J. Propuls. Power, Volume 25 (2009) no. 1, pp. 204-217
[14] An MDOE Assessment of Nozzle Vanes for High Bypass Ratio Jet Noise Reduction, 2006 (AIAA Paper, 2006–2543)
[15] Numerical analysis of the impact of the interior nozzle geometry on low Mach number jet acoustics, Flow Turbul. Combust., Volume 98 (2017) no. 2, pp. 417-443
[16] Offset Stream Technology Test – Summary of Results, 2007 (AIAA Paper, 2007–3664)
[17] Aerodynamics of fan flow deflectors for jet noise suppression, J. Propuls. Power, Volume 24 (2008) no. 3, pp. 437-445
[18] Fan flow deflection in simulated turbofan exhaust, AIAA J., Volume 44 (2006) no. 12, pp. 3088-3097
[19] Aerodynamic and Acoustic Optimization for Fan Flow Deflection, 2011 (AIAA Paper, 2011–1156)
[20] Aerodynamic performance of fan-flow deflectors for jet-noise reduction, J. Propuls. Power, Volume 28 (2012) no. 4, pp. 728-738
[21] Computation of high-speed coaxial jets with fan flow deflection, AIAA J., Volume 48 (2010) no. 10, pp. 2249-2262
[22] New insights into large eddy simulation, Fluid Dyn. Res., Volume 10 (1992) no. 4–6, pp. 199-228
[23] A comparison of second-and sixth-order methods for large-eddy simulations, Comput. Fluids, Volume 31 (2002) no. 4, pp. 695-718
[24] A strictly conservative Cartesian cut-cell method for compressible viscous flows on adaptive grids, Comput. Methods Appl. Mech. Eng., Volume 200 (2011) no. 9, pp. 1038-1052
[25] An efficient conservative cut-cell method for rigid bodies interacting with viscous compressible flows, J. Comput. Phys., Volume 311 (2016), pp. 62-86
[26] Massively parallel grid generation on HPC systems, Comput. Methods Appl. Mech. Eng., Volume 277 (2014), pp. 131-153
[27] An accurate moving boundary formulation in cut-cell methods, J. Comput. Phys., Volume 235 (2013), pp. 786-809
[28] Cut-cell method based large-eddy simulation of tip-leakage flow, Phys. Fluids, Volume 27 (2015) no. 7
[29] Hydrodynamic instability and shear layer effects in turbulent premixed combustion, Phys. Fluids, Volume 28 (2016) no. 1
[30] Computational analysis of nozzle geometry variations for subsonic turbulent jets, Comput. Fluids, Volume 136 (2016), pp. 467-484
[31] Proposed inflow/outflow boundary condition for direct computation of aerodynamic sound, AIAA J., Volume 35 (1997) no. 4, pp. 740-742
[32] Acoustic perturbation equations based on flow decomposition via source filtering, J. Comput. Phys., Volume 188 (2003) no. 2, pp. 365-398
[33] Reformulation of Acoustic Entropy Source Terms, 2011 (AIAA Paper, 2011–2927)
[34] Second-order acoustic fields: streaming with viscosity and relaxation, Phys. Rev., Volume 86 (1952) no. 4, p. 497
[35] Dispersion-relation-preserving finite difference schemes for computational acoustics, J. Comput. Phys., Volume 107 (1993) no. 2, pp. 262-281
[36] Low-dissipation and low-dispersion Runge–Kutta schemes for computational acoustics, J. Comput. Phys., Volume 124 (1996) no. 1, pp. 177-191
[37] LES-CAA coupling, Large-Eddy Simulations for Acoustics, Cambridge University Press, 2005
[38] On the simulation of trailing edge noise with a hybrid LES/APE method, J. Sound Vib., Volume 270 (2004) no. 3, pp. 509-524
[39] Collision rates of small ellipsoids settling in turbulence, J. Fluid Mech., Volume 758 (2014), pp. 686-701
[40] Computation of a high Reynolds number jet and its radiated noise using large eddy simulation based on explicit filtering, Comput. Fluids, Volume 35 (2006) no. 10, pp. 1344-1358
[41] Numerical analysis of the impact of exit conditions on low Mach number turbulent jets, Int. J. Heat Fluid Flow, Volume 67 (2017), pp. 1-12
[42] Acoustic sources and far-field noise of chevron and round jets, AIAA J., Volume 53 (2015) no. 9, pp. 2421-2436
[43] Jet noise: since 1952, Theor. Comput. Fluid Dyn., Volume 10 (1998) no. 1, pp. 393-405
[44] Juqueen: IBM Blue Gene/Q Supercomputer System at the Jülich Supercomputing Centre, J. Large-Scale Res. Facil., Volume 1 (2015) no. A1 | DOI
Cited by Sources:
Comments - Policy