Experiments in Fluids

, Volume 34, Issue 3, pp 332–344 | Cite as

Free-stream turbulence effects on the instantaneous pressure and forces on cylinders of rectangular cross section



Simultaneous measurements of instantaneous pressure distributions on rectangular cylinders of length to height ratio(B/D) of 1.0, 2.5 and 3.0 in smooth nonturbulent and homogeneous turbulent flows were made and the data were analyzed by phase averaging and spectral analysis in addition to more conventional methods. The turbulence in the inflow stream is nearly homogeneous and isotropic with the intensity and the scale of 5% and 1.2–1.5 times the cylinder height, respectively. The main effects of the turbulence in the inflow free stream of this scale and intensity are to laterally move the separated shear flow off the upstream corners and cause intermittent reattachment on the side surfaces of cylinders of B/D of 2.5 and larger. For the cylinder with smaller B/D, the flow does not reattach with or without turbulence in the free stream, and the instantaneous surface pressure distributions fluctuate quite periodically at a frequency corresponding to the Strouhal frequency of the vortex shedding. The effects of the free-stream turbulence appear in the increased fluctuation on the front surface as buffeting due to the impinging turbulence. When the separated shear layers reattach due to the influence of the free-stream turbulence, the reattachment point moves intermittently, the pressure distributions downstream of the reattachment fluctuate periodically, and a mild peak is formed in the spectra at a frequency much larger than the Strouhal frequency.


  1. Bearman PW, Obasaju ED (1982) An experimental study of pressure fluctuation on fixed and oscillating square-section cylinder. J Fluid Mech 119:297–321Google Scholar
  2. Bearman PW, Trueman DM (1972) An investigation of the flow around rectangular cylinders. Aeronaut Q 23:229–237Google Scholar
  3. Durao DFG, Heitor MV, Pereira JCF (1988) Measurement of turbulent and periodic flows around a square cross-section cylinder. Exp Fluids 6:298–304Google Scholar
  4. Ishizaki I, Katsura J (1974) On the distribution of pressure-fluctuation correlation on the side surface of two-dimensional models with slender rectangular cross sections. J Struct Constr Eng, AIJ 220:29–34 (in Japanese)Google Scholar
  5. Lee BE (1975a) The effects of turbulence on the surface pressure field of a square prism. J Fluid Mech 69:263–282Google Scholar
  6. Lee BE (1975b) Some effects of turbulence scale on the forces on a bluff body. J Ind Aerodynamics 1:361–370Google Scholar
  7. Lyn DA, Rodi W (1994) The flapping shear layer formed by flow separation from the forward corner of a square cylinder. J Fluid Mech 264:353–376Google Scholar
  8. Miyazaki M, Miyata T, Ito M (1980) Characteristics of steady and unsteady pressure distributions around a rectangular cylinder in turbulent flow. In: Proceedings of the 6th Symposium on Wind Engineering. Japan Association for Wind Engineering, Tokyo, pp177–184 (in Japanese)Google Scholar
  9. Mizota T, Okajima A (1982) On the separated flow and variation of fluid force around a rectangular cylinder with section ratio 0.4 to 1.5 in a uniform flow. In: Proceedings of the 7th Symposium on Wind Engineering. Japan Association for Wind Engineering, Tokyo, pp 75–81(in Japanese)Google Scholar
  10. Nakaguchi H, Hashimoto T, Takefuji M (1968) Experiments on drag on cylinders of rectangular cross section. Aeronaut Space Sci Jpn 16:1–5Google Scholar
  11. Nakamura Y, Ohya Y (1984) The effects of turbulence on the mean flow past two-dimensional rectangular cylinders. J Fluid Mech 149:255–273Google Scholar
  12. Okajima A (1982) Flow around cylinders of rectangular cross sections with various length to height ratios. J Wind Eng 17:75–81Google Scholar
  13. Ootsuki S, Fujii K, Washizu H, Ohya S (1980) On the characteristics of three-component aerodynamic force and pressure distribution of a fixed two-dimensional recrtangular cylinder in a uniform flow. In: Proceedings of the 6th Symposium on Wing Engineering, Japan Association for Wind Engineering, Tokyo, pp153–159 (in Japanese)Google Scholar
  14. Petty DG (1979) The effects of turbulence intensity and scale on the flow past square prisms. J Ind Aerodyn 3:247–252Google Scholar
  15. Roberson JA, Lin CY, Rutherford GS, Stine MD (1972) Turbulence effects on drag of sharp-edged bodies. ASCE J Hydraul Division HY7:187–1203Google Scholar
  16. Tamura T, Miyagi T (1988) The effects of corner shape on aerodynamic characteristics of square cylinder. J Struct Construct Eng, AIJ, No. 514:51–58 (in Japanese)Google Scholar
  17. Vickery BJ (1966) Fluctuating lift and drag on a long cylinder of square cross-section in a smooth and in a turbulent stream. J Fluid Mech 25:481–494Google Scholar
  18. Yoshida M, Hongo T, Suzuki M, Ookuma T, Marukawa H (1986) Frequency characteristics of fluctuating pressure in lead tubes. In: Proceedings of the 11th Symposium on Wind Engineering. Japan Association for Wind Engineering, Tokyo, pp 75–81(in Japanese)Google Scholar

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Technical Research InstituteMitsui Construction Co. LtdNagareyama Japan
  2. 2.Division of Global Development Science, Graduate School of Science and TechnologyKobe UniversityKobe Japan

Personalised recommendations