Wind and Structures

  • 제32권4호
  • /
  • Pages.371-391
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  • 2021
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  • 1226-6116(pISSN)
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  • 1598-6225(eISSN)
테크노프레스 (Techno-Press)
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Empirical numerical model of tornadic flow fields and load effects

  • Kim, Yong Chul (Department of Architecture, Tokyo Polytechnic University) ;
  • Tamura, Yukio (School of Civil Engineering, Chongqing University)
  • 투고 : 2020.12.08
  • 심사 : 2021.02.16
  • 발행 : 2021.04.25
⟨ 이전 논문 다음 논문 ⟩

초록

Tornadoes are the most devastating meteorological natural hazards. Many empirical and theoretical numerical models of tornado vortex have been proposed, because it is difficult to carry out direct measurements of tornado velocity components. However, most of existing numerical models fail to explain the physical structure of tornado vortices. The present paper proposes a new empirical numerical model for a tornado vortex, and its load effects on a low-rise and a tall building are calculated and compared with those for existing numerical models. The velocity components of the proposed model show clear variations with radius and height, showing good agreement with the results of field measurements, wind tunnel experiments and computational fluid dynamics. Normal stresses in the columns of a low-rise building obtained from the proposed model show intermediate values when compared with those obtained from existing numerical models. Local forces on a tall building show clear variation with height and the largest local forces show similar values to most existing numerical models. Local forces increase with increasing turbulence intensity and are found to depend mainly on reference velocity Uref and moving velocity Umov. However, they collapse to one curve for the same normalized velocity Uref / Umov. The effects of reference radius and reference height are found to be small. Resultant fluctuating force of generalized forces obtained from the modified Rankine model is considered to be larger than those obtained from the proposed model. Fluctuating force increases as the integral length scale increases for the modified Rankine model, while they remain almost constant regardless of the integral length scale for the proposed model.

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참고문헌

  1. AIJ (2015), Recommendations for Loads on Buildings, Architectural Institute of Japan; Tokyo, Japan.
  2. Baker CJ (2016), "Debris flight in tornadoes", 8th International Colloquium on Bluff Body Aerodynamics and Applications, Boston, USA, June.
  3. Bezabeh, M.A., Gairola, A., Bitsuamlak, G.T., Popovski, M. and Tesfamariam, S. (2018), "Structural performance of multi-story mass-timber buildings under tornado-like wind field", Eng. Struct., 177(15), 519- 539. https://doi.org/10.1016/j.engstruct.2018.07.079.
  4. Burgers, J.M. (1948), "A mathematical model illustrating the theory of turbulence", Advan. Appl. Mech., 1(1948), 171-199. https://doi.org/10.1016/S0065-2156(08)70100-5.
  5. Church, C.R., Snow, J.T., Baker, G.L. and Agee, E.M. (1979), "Characteristics of tornado-like vortices as a function of swirl ratio: A laboratory investigation", J. Atmos. Sci., 36(9), 1755-1776. https://doi.org/10.1175/15200469(1979)036%3C1755:COTLVA%3E2.0.CO;2.
  6. Davies Jones, R., Trapp, R.J. and Bluestein, H.B. (2001), "Tornadoes and tornadic storms", Meteor. Mon., 28(50), 167-221. https://doi.org/10.1007/978-1-935704-06-5_5.
  7. Fricker, T. (2020), "Evaluating tornado casualty rates in the United States", Int. J. Disast. Risk. Re., 47, 101535. https://doi.org/10.1016/j.ijdrr.2020.101535.
  8. Fujita, T.T. (1978), Workbook of Tornadoes and High Winds for Engineering Applications, Univ. Chicago., Chicago, Illinois, U.S.A.
  9. Haan, F.L., Sarkar, P.P. and Gallus, W.A. (2008), "Design, construction and performance of a large tornado simulator for wind engineering applications", Eng. Struct., 30(4), 1146-1159. https://doi.org/10.1016/j.engstruct.2007.07.010.
  10. Hamada, A. and El Damatty, A.A. (2016), "Behaviour of transmission line conductors under tornado wind", Wind Struct., 22(3), 369-391. https://doi.org/10.12989/was.2016.22.3.369.
  11. Hamada, A., El Damatty, A.A., Hangan, H. and Shehata, A.Y. (2010), "Finite element modelling of transmission line structures under tornado wind loading", Wind Struct., 13(5), 451. https://doi.org/10.12989/was.2010.13.5.451
  12. Hou, F. and Sarkar, P.P. (2020), "Aeroelastic model tests to study tall building vibration in boundary-layer and tornado winds", Eng. Struct., 207, 110259. https://doi.org/10.1016/j.engstruct.2020.110259.
  13. Houze, Jr, R.A. (2014), Cloud Dynamics. Academic press.
  14. Ishihara, T., Oh, S. and Tokuyama, Y. (2011), "Numerical study on flow fields of tornado-like vortices using the LES turbulence model", J. Wind Eng. Ind. Aerod., 99(4), 239-248. https://doi.org/10.1016/j.jweia.2011.01.014.
  15. Kim, Y.C. (2018), "Comparison of tornadic wind loads from various numerical expressions", International Workshop on Wind-Related Disasters and Mitigation, Paper ID 57, Sendai, Japan, March.
  16. Kim, Y.C. and Matsui, M (2017), "Analytical and empirical models of tornado vortices: A comparative study", J. Wind Eng. Ind. Aerod., 171, 230-247. https://doi.org/10.1016/j.jweia.2017.10.009.
  17. Kim, Y.C. and Tamura, Y. (2020), "Numerical modeling of one-cell tornado vortices", J. Struct. Eng., Paper ID 27.
  18. Kopp GA, Wu CH (2020), "A framework to compare wind loads on low-rise buildings in tornadoes and atmospheric boundary layers", J. Wind Eng. Ind. Aerod., 204, 104269. https://doi.org/10.1016/j.jweia.2020.104269
  19. Kosiba, K. and Wurman, J. (2010), "The three-dimensional axisymmetric wind field structure of the Spencer, South Dakota, 1998 Tornado", J. Atmos. Sci., 67(9), 3074 - 3083. https://doi.org/10.1175/2010JAS3416.1.
  20. Kosiba, K. and Wurman, J. (2013), "The three-dimensional structure and evolution of a tornado boundary layer", Weather Forecast, 28(6), 1552-1561. https://doi.org/10.1175/WAF-D-13-00070.1.
  21. Kuo, H.L. (1971), "Axisymmetric flows in the boundary layer of a maintained vortex", J. Atmos. Sci., 28(1), 20-40. https://doi.org/10.1175/15200469(1971)028%3C0020:AFITBL%3E2.0.CO;2.
  22. Le, T.H. and Caracoglia, L. (2015), "Exploring the simulation of the stochastic response of a tall building in a tornado-like wind", The 16th Asia Pacific Vibration Conference, Hanoi, Vietnam.
  23. Li, T., Yan, G., Feng, R. and Mao, X. (2020), "Investigation of the flow structure of single- and dual-celled tornadoes and their wind effects on a dome structure", Eng. Struct., 209, 109999. https://doi.org/10.1016/j.engstruct.2019.109999.
  24. Liu, M. and Matsui, M. (2018), "Measurement of three velocity components of tornado-like flow by stereo PIV and their mean velocity fields", The 25th Proceedings of National Symposium on Wind Engineering, 67-72
  25. Liu, Z. and Ishihara, T. (2016), "Study of the effects of translation and roughness on tornado-like vortices by large-eddy simulations", J. Wind Eng. Ind. Aerod., 151, 1-24. https://doi.org/10.1016/j.jweia.2016.01.006.
  26. Liu, Z., Zhang, C. and Ishihara, T. (2018), "Numerical study of the wind loads on a cooling tower by a stationary tornado-like vortex through LES", J. Fluid Struct., 81, 656-672. https://doi.org/10.1016/j.jfluidstructs.2018.06.001.
  27. McDonald, J.R. and Mehta, K.C. (2006), "A recommendation for an enhanced Fujita Scale (EF-Scale)", Wind Science Engineering Center, Texas Tech University.
  28. Natarajan, D. and Hangan, H. (2012), "Large-eddy simulations of translation and surface roughness effects on tornado-like vortices", J. Wind Eng. Ind. Aerod., 104-106, 577 - 584. https://doi.org/10.1016/j.jweia.2012.05.004.
  29. Rankine, W.J.M. (1882), A Manual of Applied Physics, Charles Griff and Co.
  30. Razavi, A. and Sarkar, P.P. (2021), "Effects of roof geometry on tornado-induced structural actions of a low-rise building", Eng. Struct., 226, 111367. https://doi.org/10.1016/j.engstruct.2020.111367.
  31. Refan, M. and Hangan, H. (2016), "Characterization of tornado-like flow fields in a new model scale wind testing chamber", J. Wind Eng. Ind. Aerod., 151, 107-121. https://doi.org/10.1016/j.jweia.2016.02.002.
  32. Refan, M., Hangan, H., Wurman, J. and Kosiba, K. (2017), "Doppler radar-derived wind field of five tornado events with application to engineering simulations", Eng. Struct., 148, 509-521. https://doi.org/10.1016/j.engstruct.2017.06.068.
  33. Ripberger, J.T., Jenkins Smith, H.C., Silva, C.L., Czajkowski, J., Kunreuther, H. and Simmons, K.M. (2018), "Tornado damage mitigation: Homeowner support for enhanced building codes in Oklahoma", Risk Anal., 38(11), 2300-2317. https://doi.org/10.1111/risa.13131.
  34. Rott, N. (1958), "On the viscous core of a line vortex", Z. Angew. Math. Phys., 9(5-6), 543-553. https://doi.org/10.1007/BF02424773.
  35. Tamura, Y., Kikuchi, H. and Hibi, K. (2008), "Peak normal stresses and effects of wind direction on wind load combinations of medium-rise buildings", J. Wind Eng. Ind. Aerod., 96(6-7), 1043-1057. https://doi.org/10.1016/j.jweia.2007.06.027.
  36. Tang, Z., Wu, L., Feng, C., Zuo, D. and James, D. (2017), "Effect of aspect ratio on tornado-like vortices simulated a large-scale tornado simulator", The 13th Americas Conference on Wind Engineering, Florida, U.S.A.
  37. Tari, P.H., Gurka, R. and Hangan, H. (2010), "Experimental investigation of tornado-like vortex dynamics with swirl ratio: the mean and turbulent flow field", J. Wind Eng. Ind. Aerod., 98(1-2), 936-944. https://doi.org/10.1016/j.jweia.2010.10.001.
  38. Wang, M., Cao, S. and Cao, J. (2020), "Tornado-like-vortex-induced wind pressure on a low-rise building with opening in roof corner", J. Wind Eng. Ind. Aerod., 205, 104308. https://doi.org/10.1016/j.jweia.2020.104308.
  39. Wen, Y.K. (1975), "Dynamic tornadic wind loads on tall buildings", J. Struct. Div., 101(ST1), 169-185. https://doi.org/10.1061/JSDEAG.0003967.