Wind and Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Experimental characterization of the lateral and near-wake flow for the BARC configuration

  • Received : 2021.04.27
  • Accepted : 2021.07.11
  • Published : 2022.01.25
⟨ Previous Next ⟩

Abstract

We experimentally investigate the high-Reynolds flow around a rectangular cylinder of aspect ratio 5:1. This configuration is the object of the international BARC benchmark. Wind tunnel tests have been carried out for the flow at zero angle of attack and a Reynolds number, based on the crossflow cylinder length and on the freestream velocity, equal, to 40 000. Velocity measurements are obtained by using hot-wire anemometry along 50 different cross-flow traverses on the cylinder side and in the near wake. Differential pressure measurements are acquired on multiple streamwise sections of the model. The obtained measurements are in a good agreement with the state-of-the-art experiments. For the first time among the several contributions to the BARC benchmark, detailed flow measurements are acquired in the region near the cylinder side and in the near-wake flow. The edges and the thickness of the shear layers detaching from the upstream edges are derived from velocity measurements. Furthermore, we compute the flow frequencies characterizing the roll-up of the shear layers, the evolution of vortical structures near the cylinder side and the vortex shedding in the wake.

Keywords

Acknowledgement

The authors wish to thank Guido Buresti for his precious suggestions in the definition of the experimental set-up. Thanks are also due to the technical staff of the Department of Civil and Industrial Engineering (Aerospace Division) for the manufacturing of the wind tunnel model and to Paolo Neri for the measurement of the radius of curvature of the upstream edges.

References

  1. Bronkhorst, A.J., Geurts, C.P.W. and van Bentum, C.A. (2011), "Unsteady pressure measurements on a 5:1 rectangular cylinder", Proceedings of the Thirteenth International Conference on Wind Engineering, Amsterdam, The Netherlands.
  2. Bruno, L., Coste, N. and Fransos, D. (2012), "Simulated flow around a rectangular 5:1 cylinder: spanwise discretisation effects and emerging flow features", J. Wind Eng. Ind. Aerod., 104-106, 203-215. https://doi.org/10.1016/j.jweia.2012.03.018.
  3. Bruno, L., Salvetti, M.V. and Ricciardelli, F. (2014), "Benchmark on the aerodynamics of a rectangular 5:1 cylinder: and 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.
  4. Buresti G., Lombardi G. and Talamelli A. (1998), "Low aspectratio triangular prisms in cross-flow: measurements of the wake fluctuating velocity field", J. Wind Eng. Ind. Aerod., 74-76, 463-473. https://doi.org/10.1016/S0167-6105(98)00042-7.
  5. Buresti, G. (1981), "The effect of surface roughness on the flow regime around circular cylinders", J. Wind Eng. Ind. Aerod., 8(1-2), 105-114. https://doi.org/10.1016/0167-6105(81)90011-8.
  6. Byrne, G., Persoons, T. and Kingston, W. (2019), "Experimental validation of lift and drag forces on an asymmetrical hydrofoil for seafloor anchoring applications", J. Ocean Climate, 9, 1-11. https://doi.org/10.1177%2F1759313118811979. https://doi.org/10.1177%2F1759313118811979
  7. Chiarini, A. and Quadrio, M. (2021), "The turbulent flow over the BARC rectangular cylinder: A DNS study", Flow, Turbulence Combustion. 1-25. https://doi.org/10.1007/s10494-021-00254-1.
  8. Cimarelli, A., Leonforte, A. and Angeli, D. (2018), "Direct numerical simulation of the flow around a rectangular cylinder at a moderately high Reynolds number", J. Wind Eng. Ind. Aerod., 174, 39-49. https://doi.org/10.1016/j.jweia.2017.12.020.
  9. Cimarelli, A., Leonforte, A. and Angeli, D. (2018), "On the structure of the self-sustaining cycle in separating and reattaching flows", J. Fluid Mech., 857, 907-936. https://doi.org/10.1017/jfm.2018.772.
  10. Dekking, M. (2018), A Modern Introduction to Probability and Statistics: Understanding Why and How, Springer
  11. Iungo G.V. and Buresti, G. (2009), "Experimental investigation on the aerodynamic loads and wake flow features of low aspectratio triangular prisms at different wind directions", J. Fluids Struct., 25(7), 1119-1135. https://doi.org/10.1016/j.jfluidstructs.2009.06.004
  12. Lamballais, E., Silvestrini, J. and Laizet, S. (2010), "Direct numerical simulation of flow separation behind a rounded leading edge: study of curvature effects", Int. J. Heat Fluid Flow, 31(3), 295-306. https://doi.org/10.1063/1.1287338.
  13. Lander, D.C., Moore, D.M., Letchford, C.W. and Amitay, M. (2018), "Scaling of square-prism shear layers", J. Fluid Mech., 849, 1096-1119. https://doi.org/10.1017/jfm.2018.443.
  14. Lunghi, G., Pasqualetto, E., Rocchio, B., Mariotti, A. and Salvetti, M.V. (2022), "Impact of the Experimental characterization of the lateral and near-wake flow for the BARC configuration", Wind Struct., 34(1). Accepted paper.
  15. Mannini, C., Mariotti, A., Siconolfi, L. and Salvetti, M.V. (2019), "Benchmark on the aerodynamics of a 5:1 Rectangular cylinder: further experimental and LES results", ERCOFTAC Series, 25, 427-432. https://doi.org/10.1007/978-3-030-04915-7_56.
  16. 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.
  17. Mannini, C., Soda, A. and Schewe, G. (2010), "Unsteady RANS modelling of flow past a rectangular cylinder: investigation of Reynolds number effects", Comput. Fluids, 39(9), 1609-1624. https://doi.org/10.1016/j.compfluid.2010.05.014.
  18. Mariotti, A. (2018), "Axisymmetric bodies with fixed and free separation: base pressure and near-wake fluctuations", J. Wind Eng. Ind. Aerod., 176, 21-31. https://doi.org/10.1016/j.jweia.2018.03.003.
  19. Mariotti, A. and Buresti, G. (2013), "Experimental investigation on the influence of boundary layer thickness on the base pressure and near-wake flow features of an axisymmetric bluntbased body", Experim. Fluids, 54(11), 1612. https://doi.org/10.1007/s00348-013-1612-5.
  20. Mariotti, A., Buresti, G. and Salvetti, M.V. (2014), "Control of the turbulent flow in a plane diffuser through optimized contoured cavities", Europ. J. Mech./B Fluids, 48, 254-265. https://doi.org/10.1016/j.euromechflu.2014.04.009.
  21. Mariotti, A., Buresti, G. and Salvetti, M.V. (2015), "Use of multiple local recirculations to increase the efficiency in diffusers", Europ. J. Mech./B Fluids, 50, 27-37. https://doi.org/10.1016/j.euromechflu.2014.11.004.
  22. Mariotti, A., Buresti, G. and Salvetti, M.V. (2019), "Separation delay through contoured transverse grooves on a 2D boat-tailed bluff body: Effects on drag reduction and wake flow features", Europ. J. Mech. B/Fluids, 74, 351-362. https://doi.org/10.1016/j.euromechflu.2018.09.009.
  23. Mariotti, A., Buresti, G., Gaggini, G. and Salvetti, M.V. (2017), "Separation control and drag reduction for boat-tailed axisymmetric bodies through contoured transverse grooves", J. Fluid Mech., 832, 514-549. https://doi.org/10.1017/jfm.2017.676.
  24. Mariotti, A., Rocchio, B., Pasqualetto, E., Mannini, C. and Salvetti, M.V. (2020), "Flow around a 5:1 rectangular cylinder: Effects of the rounding of the upstream corners", ERCOFTAC Series, 27, 85-90. https://doi.org/10.1007/978-3-030-42822-8_11.
  25. Mariotti, A., Salvetti, M.V., Shoebi-Omrani, P. and Witteveen, J.A.S. (2016), "Stochastic analysis of the impact of freestream conditions on the aerodynamics of a rectangular 5:1 cylinder", Comput. Fluids, 136, 170-192. https://doi.org/10.1016/j.compfluid.2016.06.008.
  26. Mariotti, A., Siconolfi, L. and Salvetti, M.V. (2017), "Stochastic sensitivity analysis of large-eddy simulation predictions of the flow around a 5:1 rectangular cylinder", Europ. J. Mech./B Fluids, 62, 149-165. https://doi.org/10.1016/j.euromechflu.2016.12.008.
  27. Matsumoto, M. (1996), "Aerodynamic damping of prisms", J. Wind Eng. Ind. Aerod., 59(2-3), 159-175. https://doi.org/10.1016/0167-6105(96)00005-0.
  28. Matsumoto, M., Shirato, H., Aaraki, K., Haramura, T. and Hashimoto, T. (2003), "Spanwise coherence characteristic of surface pressure field on 2D bluff bodies", J. Wind Eng. Ind. Aerod., 91, 155-163. https://doi.org/10.1016/S0167-6105(02)00342-2.
  29. Moore, D.M. and Amitay, M. (2021), "Production and migration of turbulent kinetic energy in bluff body shear layers", Int. J. Heat Fluid Flow, 88, 108716. https://doi.org/10.1016/j.ijheatfluidflow.2020.108716.
  30. Moore, D.M., Letchford, C.W. and Amitay, M. (2019), "Energetic scales in a bluff body shear layer", J. Fluid Mech., 875, 543-575. https://doi.org/10.1017/jfm.2019.480.
  31. Nguyen, D.T., Hargreaves, D.M. and Owen, J.S. (2018), "Vortexinduced vibration of a 5:1 rectangular cylinder: A comparison of wind tunnel sectional model tests and computational simulations", J. Wind Eng. Ind. Aerod., 175, 1-16. https://doi.org/10.1016/j.jweia.2018.01.029.
  32. Patruno, L., Ricci, M., de Miranda and S. and Ubertini, F. (2019), "Numerical simulation of a 5:1 rectangular cylinder at non-null angles of attack", J. Wind Eng. Ind. Aerod., 151, 146-157. https://doi.org/10.1016/j.jweia.2016.01.008.
  33. Pope, S.B. (2000), Turbulent Flows, Cambridge University Press.
  34. Ricci, M., Patruno, L., de Miranda, S. and Ubertini, F. (2017), "Flow field around a 5:1 rectangular cylinder using LES: Influence of inflow turbulence conditions, spanwise domain size and their interaction", Comput. Fluids, 149, 181-193. https://doi.org/10.1016/j.compfluid.2017.03.010.
  35. Rocchio, B. Mariotti, A. and Salvetti, M.V. (2020), "Flow around a 5:1 rectangular cylinder: Effects of upstream-edge rounding", J. Wind Eng. Ind. Aerod., 204, 104237. https://doi.org/10.1016/j.jweia.2020.104237.
  36. Schewe, G. (2013), "Reynolds-number-effects in flow around a rectangular cylinder with aspect ratio 1:5", J. Fluids Struct., 39, 15-26. https://doi.org/10.1016/j.jfluidstructs.2013.02.013.
  37. Wu, B., Li, S., Li, K. and Zhang, L. (2020), "Numerical and experimental studies on the aerodynamics of a 5:1 rectangular cylinder at angles of attack", J. Wind Eng. Ind. Aerod., 119, 104097. https://doi.org/10.1016/j.jweia.2020.104097.
  38. Yang, Y., Jones, D.L. and Liu, C. (2010), "Recovery of rectified signals from hot-wire/film anemometers due to flow reversal in oscillating flows", Rev. Sci. Instrum., 81(1), 015104. https://doi.org/10.1063/1.3277109.
  39. Zhang, Z. and Xu, F. (2020), "Spanwise length and mesh resolution effects on simulated flow around a 5:1 rectangular cylinder", J. Wind Eng. Ind. Aerod., 202, 104186. https://doi.org/10.1016/j.jweia.2020.104186.