NUMERICAL INVESTIGATION OF ROD-AIRFOIL CONFIGURATION AEROACOUSTIC CHARACTERISTICS USING FFOWCS-WILLIAMS-HAWKINGS EQUATIONS

The rod-airfoil configuration is a fundamental study to understand sound generation processes and the acoustic phenomena in the application of turbines, fans, and airfoils. In the present research, the noise that is originated by the rod-airfoil configuration is examined using numerical methods which are Large Eddy Simulation (LES), and Reynolds Averaged Navier Stokes (RANS) models, coupled with an FFOWCS-WILLIAMS-HAWKINGS (FW-H) technique. For the RANS method, k-ω SST and Spalart Allmaras (S-A) turbulence models are utilized in order to investigate the capability of different models for the analysis of the aeroacoustic flow field. The ANSYS FLUENT solver is chosen to carry out the numerical simulations. The examined rod and chord diameter Reynolds numbers are 48000 and 480000, respectively and the Mach number is 0.2. Results are obtained for both in the near field and acoustic far-field. The obtained numerical results are verified with an experimental study from the literature, and the results of both approaches are compared with each other and the experiment. Comparisons are performed for mean velocity profiles in the rod and airfoil wakes, pressure spectra and power spectral density. The results obtained show that LES is preferable for this problem as it is capable of capturing the flow separation, reattachments, vortex street, and various length scales of turbulence. Although both RANS and LES methods provide a consistent flow field with experimental methods, the RANS approach overestimates the vortex shedding frequency and Strouhal number. The RANS model predicts the flow field well; however, it overestimates the noise spectra. The LES model predicts satisfactory acoustic spectra.

Keywords:

Large Eddy Simulation(LES), , FW-H Technique Computational Fluid Dynamics Multi-zone Mesh, Noise Reduction, Noise Generation,

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[1] Casalino D., Jacob M.C., Roger M., Prediction of Rod-Airfoil Interaction Noise Using the Ffowcs-Williams-Hawkings Analogy, AIAA Journal,2008; 41: 182-191.2003.
[2] Lighthill M.J., On sound generated aerodynamically. Proc Roy Soc Lond Ser A,1952, 211, 564–87.
[3] Ffowcs Williams J.E., Hawkings D.L., Sound generated by turbulence and surfaces in arbitrary motion, Phil Trans Roy Soc, 1969, A264(1151), 321–42.
[4] Boudet J., Casalino D., Jacob M.C., Ferrand P., Unsteady RANS Computations of the Flow Past an Airfoil in the Wake of a Rod, ASME 2002 Joint U.S.-European Fluids Engineering Division Conference
[5] Berland J., Lafon P., Crouzet F., Daude F., Bailly C., Numerical Insight into Sound Sources of a Rod-Airfoil Flow Configuration Using Direct Noise Calculation, 2010, 16th AIAA/CEAS Aeroacoustics Conference,31st AIAA Aeroacoustics Conference.
[6] Jacob M.C., Boudet J., Casalino D., Michard M., A rod-airfoil experiment as a benchmark for broadband noise modeling, Theoretical and Computational Fluid Dynamics, 2005,19, 171-196.
[7] Eltaweel, A. and Wang, M., Numerical Simulation of Broadband Noise from Airfoil-Wake Interaction, 2011, 17th AIAA/CEAS Aeroacoustics Conference, AIAA.
[8] Agrawal B.J., Sharma A., Aerodynamic Noise Prediction for a Rod-Airfoil Configuration using Large Eddy Simulations, 2014,20th AIAA/CEAS Aeroacoustics Conference.
[9] Greschner B, Thiele F, Casalino D, Jacob MC., Influence of turbulence modeling on the broadband noise simulation for complex flows, AIAA, 2004,Paper No. 2004-2902.
[10] Spalart, PRaA, S1 Allmaras., A one-equation turbulence model for aerodynamic flows, In 30th aerospace sciences meeting and exhibit.
[11] Samion, S.R.L., Ali M.S.M., Aerodynamic noise measurement in anechoic wind tunnel of rod-airfoil with leading edge serrations, Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2018, 47 (1) 97-107.
[12] Galdeona S., Barre S., Reau N., Noise Radiated by rod-airfoil configuration using DES and the Ffowcs-Williams&Hawkings, 2010, In 16th AIAA/CEAS Aeroacoustics Conference.
[13] Caraeni, M., Dai, Y:, Caraeni, D., Acoustic Investigation of Rod Airfoil Configuration with DES and FWH, 37th AIAA Fluid Dynamics Conference and Exhibit, 25-28 June 2007, Miami, FL
[14] Michel, U., Eschriccht, D., Greschner, B., Knacke, T., Mockett, C., Thiele, F., Advanced DES Methods and Their Application to Aeroacoustics, Progress in Hybrid RANS-LES Modelling. Notes on Numerical Fluid Mechanics and Multidisciplinary Design, vol 111.
[15] Greschner,B., Peth, S., Moon, Y.J., Seo, J.H., Jacob, M.C., Thiele, F., Three- Dimensional Predictions of the Rod Wake-Airfoil Interaction Noise By Hybrid Methods, 14th International Conference on Sound & Vibration, ICSV14, Cairns, Australia, 2007.
[16] Laouira, H., Mubarek-Oudina, F., Hussein, A.K., Kolsi, L., Merah, A., Younis, O., Heat transfer inside a horizontal channel withan open trapezoidal enclosure subjected to aheat source of different lengths, Heat Transfer, Wıley, vol (49), pp:406-423, 2020
[17] Zhiyin Y., Large-Eddy Simulation: Past, Present and the Future, Chinese Journal of Aeronautics, 2014,28, 11-24.
[18] Ansys Fluent Manual, Fluent Inc., 2006.
[19] Gumus B., Wind Noise Prediction of a car Model Through Solutions of Navier Stokes and Ffowcs Williams&Hawkings Equations, MSc Thesis, Middle East Technical University, Ankara, TR.2017.
[20] Howell JR, Menguc MP, Siegel R. Thermal Radiation Heat Transfer. CRC Press; 2015.
[21] Fan L-S, Zhu C. Principles of Gas-Solid Flows Cambridge Series in Chemical Engineering. United Kingdom: Cambridge University Press; 2005.
[22] Otanicar T, Taylor RA, Phelan PE, Prasher R. Impact of size and scattering mode on the optimal solar absorbing nanofluid. Proc. ASME 3rd Int. Conf. Energy Sustain. 2009, ES2009, vol. 1, 2009, p. 791–6. https://doi.org/10.1115/ES2009-90066.
[23] Kocak, E., Aylı, E., Türkoğlu, H., Kanat Profili-Silindir Konfigürasyonunun Aerodinamik ve Aeroakustik Performansının Sayısal Analizi, 2019,14. Ulusal Tesisat Mühendisliği Kongresi, İzmir, Turkey.

Başlangıç: 2015
Yayıncı: YILDIZ TEKNİK ÜNİVERSİTESİ

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