DOI QR코드

DOI QR Code

Laboratory investigation of the effects of translation on the near-ground tornado flow field

  • Razavi, Alireza (Department of Aerospace Engineering, Iowa State University) ;
  • Sarkar, Partha P. (Department of Aerospace Engineering, Iowa State University)
  • 투고 : 2017.10.26
  • 심사 : 2018.01.21
  • 발행 : 2018.03.25

초록

Translation of tornadoes is an important feature in replicating the near-ground tornado flow field which has been simulated in previous studies based on Ward-type tornado simulators using relative motion of the ground plane. In this laboratory investigation, effects of translation on the near-ground tornado flow field were studied using the ISU Tornado Simulator that can physically translate over a ground plane. Two translation speeds, 0.15 m/s and 0.50 m/s, that scale up to those corresponding to slowly-moving tornadoes in the field were selected for this study. Compared with the flow field of a stationary tornado, the simulated tornado with translation had an influence on the spatial distribution and magnitude of the horizontal velocities, early reversal of the radial inflow, and expansion of the core radius. Maximum horizontal velocities were observed to occur behind the center of the translating tornado and on the right side of its mean path. An increase in translation speed, resulted in reduction of maximum horizontal velocities at all heights. Comparison of the results with previous studies that used relative motion of the ground plane for simulating translating tornadoes, showed that translation has similar effects on the flow field at smaller radial distances (~2 core radius), but different effects at larger radial distances (~4 core radius). Further, it showed that the effect of translation on velocity profiles is noticeable at and above an elevation of ~0.6 core radius, unlike those in studies based on the relative motion of the ground plane.

키워드

과제정보

연구 과제 주관 기관 : US National Science Foundation (NSF)

참고문헌

  1. Baker G.L. (1981), Boundary layers in laminar vortex flows, Ph.D. dissertation; Purdue University, West Lafayette, Indiana, USA.
  2. 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, 1755-1776. https://doi.org/10.1175/1520-0469(1979)036<1755:COTLVA>2.0.CO;2
  3. Davies-Jones R.P. (1973), "The dependence of core radius on swirl ratio in a tornado simulator", J. Atmos. Sci., 30, 1427-1430. https://doi.org/10.1175/1520-0469(1973)030<1427:TDOCRO>2.0.CO;2
  4. Dessens Jr. J. (1972), "Influence of ground roughness on tornadoes. A laboratory simulation", J. Appl. Meteorol., 11, 72-75. https://doi.org/10.1175/1520-0450(1972)011<0072:IOGROT>2.0.CO;2
  5. Diamond C.J. and Wilkins E.M. (1984), "Translation effects on simulated tornadoes", J. Atmos. Sci., 41(17), 2574-2580. https://doi.org/10.1175/1520-0469(1984)041<2574:TEOST>2.0.CO;2
  6. Haan Jr. 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, 1146-1159. https://doi.org/10.1016/j.engstruct.2007.07.010
  7. Hashemi Tari P., Gurka R. and Hangan H. (2010), "Experimental investigation of tornado-like vortex dynamics with swirl ratio: The mean and turbulent flow fields. J. Wind Eng. Ind. Aerod., 98(12), 936-944. https://doi.org/10.1016/j.jweia.2010.10.001
  8. Jischke M.C. and Parang M. (1974), "Properties of simulated tornado-like vortices", J. Atmos. Sci., 34, 1022-1027.
  9. Karstens C.D., Samaras T.M., Lee B.D. and Finley C.A. (2010), "Near-ground pressure and wind measurements in tornadoes", Mon. Weather Rev., 138, 2570-2588. https://doi.org/10.1175/2010MWR3201.1
  10. Kosiba K.A., Trapp R.J. and Wurman J. (2008), "An analysis of the axisymmetric three-dimensional low-level wind field in a tornado using mobile radar observation", Geophys. Res. Lett., 35, L05805, 1-6. doi:10.1029/2007GL031851.
  11. Lee W. and Wurman J. (2005), "Diagnosed three-dimensional axisymmetric structure of the Mulhall tornado on 3 May 1999", J. Atmos. Sci., 62, 2373-2393. https://doi.org/10.1175/JAS3489.1
  12. Leslie F.W. (1977), "Surface roughness effects on suction vortex formation: a laboratory simulation", J. Atmos. Sci., 34, 1022-1027. https://doi.org/10.1175/1520-0469(1977)034<1022:SREOSV>2.0.CO;2
  13. Lewellen W.S. (1963), "A solution for three-dimensional vortex flows with strong circulation", J. Fluid. Mech., 14, 420-432.
  14. Lewellen W.S., Lewellen D.C. and Sykes R.I. (1997)), "Largeeddy simulation of a tornado's interaction with the surface", J. Atmos. Sci., 54(5), 581-605. https://doi.org/10.1175/1520-0469(1997)054<0581:LESOAT>2.0.CO;2
  15. Liu Z. and Ishihara T. (2016), "Study f the effects of translation and roughness on tornado-like vortices by large-eddy simulation", J. Wind Eng. Ind. Aerod., 151, 1-24. https://doi.org/10.1016/j.jweia.2016.01.006
  16. Natarajan D. and Hangan H. (2012), "Large eddy simulation 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
  17. Razavi A. and Sarkar P. (2016), "Laboratory investigation of the effects of tornado translation on its near-ground flow field", Proceedings of the 8th international colloquium on bluff body aerodynamics and applications, June 7-11, Boston, Massachusetts, USA.
  18. 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
  19. Rotunno R. (1977), "Numerical simulation of a laboratory vortex", J. Atmos. Sci., 34, 1942-1956. https://doi.org/10.1175/1520-0469(1977)034<1942:NSOALV>2.0.CO;2
  20. Ward N.B. (1972), "The exploration of certain features of tornado dynamics using a laboratory model", J. Atmos. Sci., 29, 1194-1204. https://doi.org/10.1175/1520-0469(1972)029<1194:TEOCFO>2.0.CO;2
  21. Wurman J. and Alexander C.R. (2005), "The 30 May 1999 Spencer, South Dakota, storm. Part II: comparison of observed damage and radar-derived winds in the tornadoes", Mon. Weather Rev., 133, 97-119. https://doi.org/10.1175/MWR-2856.1

피인용 문헌

  1. System simulation and synchronization for optimal evolutionary design of nonlinear controlled systems vol.26, pp.6, 2018, https://doi.org/10.12989/sss.2020.26.6.797
  2. Modified algorithmic LMI design with applications in aerospace vehicles vol.8, pp.1, 2018, https://doi.org/10.12989/aas.2021.8.1.069
  3. Optimized AI controller for reinforced concrete frame structures under earthquake excitation vol.11, pp.1, 2021, https://doi.org/10.12989/acc.2021.11.1.001