Wind and Structures

  • 제19권1호
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  • Pages.89-111
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  • 2014
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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

Numerical study on dynamics of a tornado-like vortex with touching down by using the LES turbulence model

  • Ishihara, Takeshi (Department of Civil Engineering, School of Engineering, The University of Tokyo) ;
  • Liu, Zhenqing (Department of Civil Engineering, School of Engineering, The University of Tokyo)
  • 투고 : 2012.09.10
  • 심사 : 2014.05.18
  • 발행 : 2014.07.25
⟨ 이전 논문 다음 논문 ⟩

초록

The dynamics of a tornado-like vortex with touching down is investigated by using the LES turbulence model. The detailed information of the turbulent flow fields is provided and the force balances in radial and vertical directions are evaluated by using the time-averaged axisymmetric Navier-Stokes equations. The turbulence has slightly influence on the mean flow fields in the radial direction whereas it shows strong impacts in the vertical direction. In addition, the instantaneous flow fields are investigated to clarify and understand the dynamics of the vortex. An organized swirl motion is observed, which is the main source of the turbulence for the radial and tangential components, but not for the vertical component. Power spectrum analysis is conducted to quantify the organized swirl motion of the tornado-like vortex. The gust speeds are also examined and it is found to be very large near the center of vortex.

키워드

참고문헌

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피인용 문헌

  1. Numerical study of turbulent flow fields and the similarity of tornado vortices using large-eddy simulations vol.145, 2015, https://doi.org/10.1016/j.jweia.2015.05.008
  2. Study of the effects of translation and roughness on tornado-like vortices by large-eddy simulations vol.151, 2016, https://doi.org/10.1016/j.jweia.2016.01.006
  3. A local analysis of the axisymmetric Navier–Stokes flow near a saddle point and no-slip flat boundary vol.794, 2016, https://doi.org/10.1017/jfm.2016.174
  4. Numerical study of tornado-borne debris on a low-rise building through large eddy simulation vol.106, pp.None, 2014, https://doi.org/10.1016/j.jfluidstructs.2021.103379