Wind and Structures

  • 제27권1호
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  • Pages.11-27
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  • 2018
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  • 1226-6116(pISSN)
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  • 1598-6225(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

A study on the action mechanism of internal pressures in straight-cone steel cooling tower under two-way coupling between wind and rain

  • Ke, S.T. (Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics) ;
  • Du, L.Y. (Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics) ;
  • Ge, Y.J. (State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University) ;
  • Yang, Q. (Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics) ;
  • Wang, H. (School of Civil Engineering, Southeast University) ;
  • Tamura, Y. (Center of Wind Engineering Research, Tokyo Polytechnic University)
  • 투고 : 2017.08.05
  • 심사 : 2018.02.27
  • 발행 : 2018.07.25
⟨ 이전 논문 다음 논문 ⟩

초록

The straight-cone steel cooling tower is a novel type of structure, which has a distinct aerodynamic distribution on the internal surface of the tower cylinder compared with conventional hyperbolic concrete cooling towers. Especially in the extreme weather conditions of strong wind and heavy rain, heavy rain also has a direct impact on aerodynamic force on the internal surface and changes the turbulence effect of pulsating wind, but existing studies mainly focus on the impact effect brought by wind-driven rain to structure surface. In addition, for the indirect air cooled cooling tower, different additional ventilation rate of shutters produces a considerable interference to air movement inside the tower and also to the action mechanism of loads. To solve the problem, a straight-cone steel cooling towerstanding 189 m high and currently being constructed is taken as the research object in this study. The algorithm for two-way coupling between wind and rain is adopted. Simulation of wind field and raindrops is performed with continuous phase and discrete phase models, respectively, under the general principles of computational fluid dynamics (CFD). Firstly, the rule of influence of 9 combinations of wind sped and rainfall intensity on flow field mechanism, the volume of wind-driven rain, additional action force of raindrops and equivalent internal pressure coefficient of the tower cylinder is analyzed. On this basis, the internal pressures of the cooling tower under the most unfavorable working condition are compared between four ventilation rates of shutters (0%, 15%, 30% and 100%). The results show that the 3D effect of equivalent internal pressure coefficient is the most significant when considering two-way coupling between wind and rain. Additional load imposed by raindrops on the internal surface of the tower accounts for an extremely small proportion of total wind load, the maximum being only 0.245%. This occurs under the combination of 20 m/s wind velocity and 200 mm/h rainfall intensity. Ventilation rate of shutters not only changes the air movement inside the tower, but also affects the accumulated amount and distribution of raindrops on the internal surface.

키워드

과제정보

연구 과제 주관 기관 : National Natural Science Foundation, Jiangsu Province Natural Science Foundation, Postdoctoral Science Foundation

참고문헌

  1. Bennett, M., Kodakalla, V. and Gupta, V. (2011), "Vibration mitigation measures in cable stayed bridges", J. Molecular Struct. 996(1-3), 64-68. https://doi.org/10.1016/j.molstruc.2011.04.017
  2. Blocken, B., Dezso, G., Beeck, J.V. and Carmeliet, J. (2010), "Comparison of calculation models for wind-driven rain deposition on building facades", Atmosp. Environ., 44(14), 1714-1725. https://doi.org/10.1016/j.atmosenv.2010.02.011
  3. Blocken, B. and Carmeliet, J. (2004), "A Review of Wind-Driven Rain Research in Building Science", J. Wind Eng. Ind. Aerod., 92, 1079-1130. https://doi.org/10.1016/j.jweia.2004.06.003
  4. Blocken, B. and Carmeliet, J. (2002), "Spatial and temporal distribution of driving rain on alow-rise building", Wind Struct., 5(5), 441-462. https://doi.org/10.12989/was.2002.5.5.441
  5. BS4485(Part 4) (1996), Code of practice for structural design and construction-water cooling tower. London: British Standard Institution.
  6. Cheng, X.X., Zhao, L. and Ge, Y.J. (2013), "Multiple loading effects on wind-induced static performance of super-large cooling towers", Int. J. Struct. Stab. Dynam., 13(8).
  7. DL/T 5339-2006 (2006), Code for hydraulic design of fossil fuel power plants. The Ministry of Construction of China, Beijing, China, 115-116. (in Chinese)
  8. Dong, G.C., Zhang, J.R., Cai, C.S. and Han Y. (2016), "Study on internal surface pressure coefficient of super-large cooling tower with different internal main components", Eng. Mech., 33(4), 77-83. (in Chinese)
  9. Douvi, E. and Margaris, D. (2012), "Aerodynamic performance investigation under the influence of heavy rain of a NACA 0012 airfoil for wind turbine applications", Int. Rev. Mech. Eng., 6(6).
  10. Du, L.Y. and Ke, S.T. (2016), "Research on effect of internal pressures for super large cylinder-conic section steel cooling towers", J. Central south University, accepted, forthcoming. (in Chinese)
  11. Fu, X., Li, H.N. and Li, G. (2016), "Fragility analysis and estimation of collapse status for transmission tower subjected to wind and rain loads", Struct. Saf., 58, 1-10. https://doi.org/10.1016/j.strusafe.2015.08.002
  12. GB50009-2012 (2012), Load code for the design of building structures. The Ministry of Construction of China, Beijing, China, 35-36. (in Chinese)
  13. Goudarzi, M.A. and Sabbagh-Yazdi, S.R. (2011), "Effects of modeling strategy on computational wind pressure distribution around the cooling towers", Wind Struct., 14(1), 81-84. https://doi.org/10.12989/was.2011.14.1.081
  14. Gunn, R. and Kinzer, G.D. (1949), "The terminal fall velocity for water droplets in stagnant air", J. Atmos. Sci., 6(4), 243-248.
  15. Ke, S.T., Ge, Y.J., Zhao, L. and Tamura, Y. (2015), "Stability and reinforcement analysis of super large exhaust cooling towers based on a wind tunnel test", J. Struct. Eng., 141(12), 04015066. https://doi.org/10.1061/(ASCE)ST.1943-541X.0001309
  16. Ke, S.T., Liang, J., Zhao, L. and Ge, Y.J. (2015), "Influence of ventilation rate on the aerodynamic interference for two IDCTs by CFD", Wind Struct., 20(3), 449-468. https://doi.org/10.12989/was.2015.20.3.449
  17. Li, L.X., Kareem, A., Xiao, Y.Q. and Zhou, C. (2015), "A comparative study of field measurements of the turbulence characteristics of typhoon and hurricane winds", J. Wind Eng. Ind. Aerod., 140, 49-66. https://doi.org/10.1016/j.jweia.2014.12.008
  18. Liu, S., Huang, S.H. and Li, Q.S. (2017), "3D numerical simulation of wind-driven rain on bridge deck sections based on eulerian multiphase model", Eng. Mech., 34(4), 63-71. (in Chinese)
  19. Marshall, J.S. and Palmer, W.M. (1948), "The distribution of raindrops with size", J. Meteorology, 5, 165-166. https://doi.org/10.1175/1520-0469(1948)005<0165:TDORWS>2.0.CO;2
  20. Mcfarquhar, G.M. and List, R. (2010), "The raindrop mean free path and collision rate dependence on rainrate for three-peak equilibrium and marshall-palmer distributions", J. Atmos. Sci., 48(48), 1999-2004.
  21. Rigby, E.C., Marshall, J.S. and Hitschfeld, W. (2010), "The development of the size distribution of raindrops during their fall", J. Atmo. Sci., 11(5), 362-372.
  22. VGB-R610Ue (2005), VGB-Guideline: structural design of cooling tower-technical guideline for the structural design, computation and execution of cooling towers. Essen: BTR Bautechnik Bei Kuhlturmen.
  23. Wang, L.Y. and Xu, Y.L. (2010), "Active stiffness control of windrain-induced vibration of prototype stay cable", Int. J. Numer. Method. Eng., 74(1), 80-100. https://doi.org/10.1002/nme.2152
  24. Wang, Z., Zhao, Y., Li, F. and Jiang, J. (2013), "Extreme dynamic responses of mw-level wind turbine tower in the strong typhoon considering wind-rain loads", Math. Probl. Eng., 3, 133-174.
  25. Xin, D., Li, H., Wang, L. and Ou, J. (2012), "Experimental study on static characteristics of the bridge deck section under simultaneous actions of wind and rain", J. Wind Eng. Ind. Aerod., s(107-108), 17-27.
  26. Zhang, Q.C., Li, W.Y. and Wang, W. (2010), "Static bifurcation of rain-wind-induced vibration of stay cable", Acta Physica Sinica, 59(2), 729-734.