Numerical Investigation of Flow Induced Sound Around a Square Cylinder at Various Incidence Angles

Document Type : Original Article

Authors

• mohsen mohammadrezaei ¹
• Ali Akbar Dehghan ²
• Alireza Movahedi ³

¹ Yazd university

² Yazd University

³ Yazd

10.22067/fum-mech.v29i1.50734

Abstract

Flow characteristics and sound pressure level in the acoustical far field and on the surface of a square cylinder at incidence are investigated for six angles of attacks. Flow around square cylinder is modeled using large eddy simulation method. The flow simulation is conducted using fluent commercial software. The results of the present study showed good agreement with the available experimental results. The minimum of drag coefficient, mean and root mean squared (rms) value of lift coefficient, and sound pressure level in acoustical far field occurred at 13o angle of attack which is due to the lowest values of fluctuating lift and drag forces at this angle of attack. The induced acoustic field is due to the fluctuating lift force acting on the rod.

Keywords

• Square cylinder
• sound pressure level
• turbulence
• large eddy simulation

---

References

1. Becker, S., Escobar, M., Hahn, C., Ali, I., Kaltenbachery, M., Baselz, B. and Grunewaldz, M.,"Experimental and Numerical Investigation of the Flow Induced Noise from a Forward Facing Step", 11th AIAA/CEAS Aeroacoustics Conference, Montorey, California, 23-25 May, (2005.(

2. Dorneanu, J.F., " Tonal and silent wake modes of a square rod at incidence ", ACTA Acustica United with Acustica, Vol. 102, No. 3, pp. 419-422, 2016.

3. Vickery, B.J. , "Fluctuating lift and drag on a long cylinder of square cross-section in a smooth and in a turbulent stream", Fluid Mechanic, Vol. 25, pp. 481-494,1996.

4. Bearman, P.W. and Obasaju, E.D., "An experimental study of pressure fluctuations on fixed and oscillating square section cylinders", Journal of Fluid Mechanics, Vol 119, pp. 297-321, (1981).

5. Igarashi, T., "Characteristics of the flow around a square prism", Bulletin of JSME, Vol. 27, (1984).

6. Knisely, C.W.,"strouhal numbers of rectangular cylinders at incidence-A review and new data", Journal of Fluids and Structures, Vol 4, No. 4, (1990)

7. Norberg, C.,"Flow around rectangular cylinders Pressure forces and wake frequencies", Journal of Wind Engineering and Industrial Aerodynamics, Vol. 49, No. 1, pp. 187-196, (1993)

8. Rodi, W.,"Comparison of LES and RANS calculations of the flow around bluff bodies", Journal of Wind Engineering and Industrial Aerodynamics, Wind Eng. 67, pp.65-78,(1997)

9. Fujita, H., Sha, W., Furutani, H. and Suzuki, H., "Experimental investigations and prediction of arerodynamic sound generated from square cylinders", in 4th AIAA/CEAS Aeroacoustics Conference, Toulouse, France, AIAA Paper, Toulouse, France, 19-21 August, (1998).

10. Tamura, T. and Miyagi, T., "The efect of turbulence on aerodynamic forces on a square cylinder with various corner shapes", Journal of Wind Engineering and Industrial Aerodynamics, pp. 135-145, (1999).

11. Chen, J.M. and Liu, C-H, "Vortex shedding and surface pressures on a square cylinder at incidence to a uniform air stream", International Journal of Heat and Fluid Flow, (1999).

12. Hutcheson, F.V. and Thomas, F.B.,"Noise Radiation from Single and Multiple Rod Configurations", International Journal of Aeroacoustics, Vol. 11, No. 3, pp. 291-333, 2012.

13. Mueller,A.,"Large Eddy Simulation of Cross-Flow Around a Square Rod at Incidence with Application to Tonal Noise Prediction", PhD Thesis ,University of Twente, Holland, (2012).

14. Williams, J.E.F. and Hawkings, D.L., "Sound Generation By Turbulence And Surfaces In Arbitfrary Motion", Philosophical Transactions of the Royal Society of London A: Mathematical, Physical and Engineering Sciences, 264(1151): p. 321-342, (1968).

15. Lighthill, M.J.,"On Sound Generated Aerodynamically. I. General Theory", Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 211, No. 1107, pp. 564-587, (1952).

16. Daniel, A.R., Titlow, J.P. and Bemmen, Y.J, "Acoustic monopoles, dipoles, and quadrupoles: An experiment revisited", American journal of physics, (1999).

17. Rienstra, S. W. and Hirschberg, A., "An Introduction to Acoustics", PhD Thesis, Eindhoven University of Technology, Netherlands, (2013).

18. Lai, C.H. and Jiang, Xi, "Numerical Techniques for Direct and Large Eddy Simulations", CRC Press, (2009).

19. Lesieur, M., "Turbulence in Fluids", 4th Edition, Springer Science & Buisiness Media, (2008).

20. Wang, Y.P., Chen, J., Lee, H.C. and Li, K.M., "Accurate simulations of surface pressure fluctuations and flow-induced noise near bluff body at low Mach numbers", The Seventh International Colloquium on Bluff Body Aerodynamics and Applications, Shanghai, China, (2012).

21. Sukri Mat, M., Shaikh Salim,S., Ismail,M., Muhamad,S. and Iyas,M. "Aeolian Tones Radiated from Flow Over Bluff Bodies", The Open Mechanical Engineering Journal, Vol. 7, No. 1, pp. 48-57, (2013).

22. Mohammadrezaei, M., Dehghan, A. and Movahedi, A., "Numerical investigation of sound pressure level over a forward facing step using large eddy simulation", 23rd Annual International Mechanical Engineering Conference, Tehran, Iran,12-14 May, (2015).