Wind and Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Fluctuating lift and drag acting on a 5:1 rectangular cylinder in various turbulent flows

  • Yang, Yang (Research Centre for Wind Engineering, Southwest Jiaotong University) ;
  • Li, Mingshui (Research Centre for Wind Engineering, Southwest Jiaotong University) ;
  • Yang, Xiongwei (Research Centre for Wind Engineering, Southwest Jiaotong University)
  • Received : 2021.04.07
  • Accepted : 2021.10.17
  • Published : 2022.01.25
⟨ Previous Next ⟩

Abstract

In this paper, the fluctuating lift and drag forces on 5:1 rectangular cylinders with two different geometric scales in three turbulent flow-fields are investigated. The study is particularly focused on understanding the influence of the ratio of turbulence integral length scale to structure characteristic dimension (the length scale ratio). The results show that both fluctuating lift and drag forces are influenced by the length scale ratio. For the model with the larger length scale ratio, the corresponding fluctuating force coefficient is larger, while the spanwise correlation is weaker. However, the degree of influence of the length scale ratio on the two fluctuating forces are different. Compared to the fluctuating drag, the fluctuating lift is more sensitive to the variation of the length scale ratio. It is also found through spectral analysis that for the fluctuating lift, the change of length scale ratio mainly leads to the variation in the low frequency part of the loading, while the fluctuating drag generally follows the quasi-steady theory in the low frequency, and the slope of the drag spectrum at high frequencies changes with the length scale ratio. Then based on the experimental data, two empirical formulas considering the influence of length scale ratio are proposed for determining the lift and drag aerodynamic admittances of a 5:1 rectangular cylinder. Furthermore, a simple relationship is established to correlate the turbulence parameter with the fluctuating force coefficient, which could be used to predict the fluctuating force on a 5:1 rectangular cylinder under different parameter conditions.

Keywords

Acknowledgement

The work is supported by the National Natural Science Foundation of China under Grant nos. 52008357, 51878580 and the Fundamental Research Funds for the Central Universities with project no. 2682021CX006.

References

  1. Bartoli, G., Bruno, L., Buresti, G., Ricciardelli, F., Salvetti, M.V. and Zasso, A. (2009), "BARC: a benchmark on the aerodynamics of a rectangular 5:1 cylinder", J. Fluids Struct., 25, 586. https://doi.org/10.1016/j.jfluidstructs.2008.11.003.
  2. Bearman, P.W. (1971), "An investigation of the forces on flat plates normal to a turbulent flow", J. Fluid Mech., 46, 177-198. https://doi.org/10.1017/S0022112071000478.
  3. Bearman, P.W. (1972), "Some measurements of the distortion of turbulence approaching a two-dimensional bluff body", J. Fluid Mech., 53(3), 451-467. https://doi.org/10.1017/S0022112072000254.
  4. Bearman, P.W. and Morel, T. (1983), "Effect of free stream turbulence on the flow around bluff bodies", Prog. Aerosp. Sci., 20, 97-123. https://doi.org/10.1016/0376-0421(83)90002-7.
  5. Bruno, L., Salvetti, M.V. and Ricciardelli, F. (2014), "Benchmark on the aerodynamics of a rectangular 5:1 cylinder: an overview after the first four years of activity", J. Wind Eng. Ind. Aerod., 126, 87-106. https://doi.org/10.1016/j.jweia.2014.01.005.
  6. Durbin, P.A. and Hunt, J.C.R. (1980), "On surface pressure fluctuations beneath turbulent flow around bluff bodies", J. Fluid Mech., 100(1), 161-184. https://doi.org/10.1017/S0022112080001061.
  7. Emes, M.J., Arjomandi, M., Ghanadi, F. and Kelso, R.M. (2017), "Effect of turbulence characteristics in the atmospheric surface layer on the peak wind loads on heliostats in stow position", Sol. Energy, 157, 284-297. https://doi.org/10.1016/j.solener.2017.08.031.
  8. Hillier, R. and Cherry, N.J. (1981), "The effects of stream turbulence on separation bubbles", J. Wind Eng. Ind. Aerod., 8(1), 49-58. https://doi.org/10.1016/0167-6105(81)90007-6.
  9. Holscher, N. and Niemann, J. (1998), "Towards quality assurance for wind tunnel tests: a comparative testing program of the Windtechnologische Gesellschaft", J. Wind Eng. Ind. Aerod., 74, 599-608. https://doi.org/10.1016/S0167-6105(98)00054-3.
  10. Hunt, J.C.R. (1973), "A theory of turbulent flow round two-dimensional bluff bodies", J. Fluid Mech., 61(4), 625-706. https://doi.org/10.1017/S0022112073000893.
  11. Ito, Y., Shirato, H. and Matsumoto, M. (2014), "Coherence characteristics of fluctuating lift forces for rectangular shape with various fairing decks", J. Wind Engng Ind. Aerod., 135, 34-45. https://doi.org/10.1016/j.jweia.2014.10.003.
  12. Jafari, A., Ghanadi, F., Arjomandi, M., Emes, M.J. and Cazzolato, B.S. (2019), "Correlating turbulence intensity and length scale with the unsteady lift force on flat plates in an atmospheric boundary layer flow", J. Wind Eng. Ind. Aerod., 189, 218-230. https://doi.org/10.1016/j.jweia.2019.03.029.
  13. Jakobsen, J.B. (1997), "Span-wise structure of lift and overturning moment on a motionless bridge girder", J. Wind Engng Ind. Aerod., 71, 795-805. https://doi.org/10.1016/S0167-6105(97)00206-7.
  14. Kimura, K., Fujino, Y., Nakato, S. and Tamura, H. (1997), "Characteristics of buffeting forces on flat cylinders", J. Wind Engng Ind. Aerod., 71, 365-374. https://doi.org/10.1016/S0167-6105(97)00169-4.
  15. Kiya, M. and Sasaki, K. (1983), "Free-stream turbulence effects on a separation bubble", J. Wind Eng. Ind. Aerod., 14(3), 375-386. https://doi.org/10.1016/0167-6105(83)90039-9.
  16. Larose, G.L. (1999), "Experimental determination of the aerodynamic admittance of a bridge deck segment", J. Fluids Struct., 13, 1029-1040. https://doi.org/10.1006/jfls.1999.0244.
  17. Larose, G.L. and Mann, J. (1998), "Gust loading on streamlined bridge decks", J. Fluids Struct., 12, 511-536. https://doi.org/10.1006/jfls.1998.0161.
  18. Lavoie, P., Djenidi, L. and Antonia, R.A. (2007), "Effects of initial conditions in decaying turbulence generated by passive grids", J. Fluid Mech., 585, 395-420. https://doi.org/10.1017/S0022112007006763.
  19. Li, M., Yang, Y., Li, M. and Liao, H. (2018), "Direct measurement of the Sears function in turbulent flow", J. Fluid Mech., 847, 768-785. https://doi.org/10.1017/jfm.2018.351.
  20. Li, Q.S. and Melbourne, W.H. (1995), "An experimental investigation of the effects of freestream turbulence on streamwise surface pressures in separated and reattaching flows", J. Wind Eng. Ind. Aerod., 54, 313-323. https://doi.org/10.1016/0167-6105(94)00050-N.
  21. Li, S. and Li, M. (2017), "Spectral analysis and coherence of aerodynamic lift on rectangular cylinders in turbulent flow", J. Fluid Mech., 830, 408-438. https://doi.org/10.1017/jfm.2017.593.
  22. Mannini, C., Marra, A.M., Pigolotti, L. and Bartoli, G. (2017), "The effects of free-stream turbulence and angle of attack on the aerodynamics of a cylinder with rectangular 5:1 cross section", J. Wind Eng. Ind. Aerod., 161, 42-58. https://doi.org/10.1016/j.jweia.2016.12.001.
  23. Massaro, M. and Graham, J.M.R. (2015), "The effect of three-dimensionality on the aerodynamic admittance of thin sections in free stream turbulence", J. Fluid Struct., 57, 81-89. https://doi.org/10.1016/j.jfluidstructs.2015.05.012.
  24. Nakamura, Y. and Ohya, Y. (1984), "The effects of turbulence on the mean flow past two-dimensional rectangular cylinders", J. Fluid Mech., 149, 255-273. https://doi.org/10.1017/S0022112084002640.
  25. Nakamura, Y. and Ozono, S. (1987), "The effects of turbulence on a separated and reattaching flow", J. Fluid Mech., 178, 477-490. https://doi.org/10.1017/S0022112087001320.
  26. Peterka, J.A., Tan, Z., Cermak, J.E. and Bienkiewicz, B. (1989), "Mean and peak wind loads on heliostats", J. Sol. Energy Eng., 111, 158-164. https://doi.org/10.1115/1.3268302.
  27. Pfahl, A., Buselmeier, M. and Zaschke, M. (2011), "Wind loads on heliostats and photovoltaic trackers of various aspect ratios", Sol. Energy, 85, 2185-2201. https://doi.org/10.1016/j.solener.2011.06.006.
  28. Pfahl, A., Randt, M., Meier, F., Zaschke, M., Geurts, C.P.W., Buselmeier, M. (2015), "A holistic approach for low cost heliostat fields", Energy Procedia, 69, 178-187. https://doi.org/10.1016/j.egypro.2015.03.021.
  29. Rasmussen, J.T., Hejlesen, M.M., Larsen, A. and Walther, J.H. (2010), "Discrete vortex method simulations of the aerodynamic admittance in bridge aerodynamics", J. Wind Eng. Ind. Aerod., 98, 754-766. https://doi.org/10.1016/j.jweia.2010.06.011.
  30. Saathoff, P.J. and Melbourne, W.H. (1987), "Freestream turbulence and wind tunnel blockage effects on streamwise surface pressures", J. Wind Eng. Ind. Aerod., 26, 353-370. https://doi.org/10.1016/0167-6105(87)90005-5.
  31. Scanlan, R.H. (1978), "The action of flexible bridges under wind II: buffeting theory", J. Sound Vib, 60, 201-211. https://doi.org/10.1016/S0022-460X(78)80029-7.
  32. Simiu, E. and Yeo, D. (2019), Wind Effects on Structures: Fundamentals and Applications to Design, John Wiley and Sons, New York, U.S.A.
  33. Stathopoulos, T. and Surry, D. (1983), "Scale effects in wind tunnel testing of low buildings", J. Wind Eng. Ind. Aerod., 13, 313-326. https://doi.org/10.1016/B978-0-444-42340-5.50038-5.
  34. Yang, Y., Li, M., Su, Y. and Sun, Y. (2019), "Aerodynamic admittance of a 5:1 rectangular cylinder in turbulent flow", J. Wind Eng. Ind. Aerod., 189, 125-134. https://doi.org/10.1016/j.jweia.2019.03.023.