DOI QR코드

DOI QR Code

The appropriate shape of the boundary transition section for a mountain-gorge terrain model in a wind tunnel test

  • Hu, Peng (School of Civil Engineering and Architecture, Changsha University of Science & Technology) ;
  • Li, Yongle (School of Civil Engineering, Southwest Jiaotong University) ;
  • Huang, Guoqing (School of Civil Engineering, Southwest Jiaotong University) ;
  • Kang, Rui (Department of Civil Engineering, Southwest Jiaotong University) ;
  • Liao, Haili (School of Civil Engineering, Southwest Jiaotong University)
  • Received : 2014.03.14
  • Accepted : 2014.11.01
  • Published : 2015.01.25

Abstract

Characterization of wind flows over a complex terrain, especially mountain-gorge terrain (referred to as the very complex terrain with rolling mountains and deep narrow gorges), is an important issue for design and operation of long-span bridges constructed in this area. In both wind tunnel testing and numerical simulation, a transition section is often used to connect the wind tunnel floor or computational domain bottom and the boundary top of the terrain model in order to generate a smooth flow transition over the edge of the terrain model. Although the transition section plays an important role in simulation of wind field over complex terrain, an appropriate shape needs investigation. In this study, two principles for selecting an appropriate shape of boundary transition section were proposed, and a theoretical curve serving for the mountain-gorge terrain model was derived based on potential flow theory around a circular cylinder. Then a two-dimensional (2-D) simulation was used to compare the flow transition performance between the proposed curved transition section and the traditional ramp transition section in a wind tunnel. Furthermore, the wind velocity field induced by the curved transition section with an equivalent slope of $30^{\circ}$ was investigated in detail, and a parameter called the 'velocity stability factor' was defined; an analytical model for predicting the velocity stability factor was also proposed. The results show that the proposed curved transition section has a better flow transition performance compared with the traditional ramp transition section. The proposed analytical model can also adequately predict the velocity stability factor of the wind field.

Keywords

Acknowledgement

Supported by : National Natural Science Foundation of China

References

  1. Bowen, A.J. (2003), "Modelling of strong wind flows over complex terrain at small geometric scales", J. Wind Eng. Ind. Aerod., 91(12-15), 1859-1871. https://doi.org/10.1016/j.jweia.2003.09.029
  2. Bowen, A.J. and Lindley, D. (1977), "A wind-tunnel investigation of the wind speed and turbulence characteristics close to the ground over various escarpment shapes", Bound. - Lay. Meteorol., 12(3), 259-271. https://doi.org/10.1007/BF00121466
  3. Cao, S. and Tamura, T. (2006), "Experimental study on roughness effects on turbulent boundary layer flow over a two-dimensional steep hill", J. Wind Eng. Ind. Aerod., 94(1), 1-19. https://doi.org/10.1016/j.jweia.2005.10.001
  4. Carpenter, P. and Locke, N. (1999), "Investigation of wind speeds over multiple two-dimensional hills", J. Wind Eng. Ind. Aerod., 83(1-3), 109-120. https://doi.org/10.1016/S0167-6105(99)00065-3
  5. Cermak, J.E. (1984), "Physical modelling of flow and dispersion over complex terrain", Bound. - Lay. Meteorol., 30(1-4), 261-292. https://doi.org/10.1007/BF00121957
  6. Chock, G.Y.K. and Cochran, L. (2005), "Modeling of topographic wind speed effects in Hawaii", J. Wind Eng. Ind. Aerod., 93(8), 623-638. https://doi.org/10.1016/j.jweia.2005.06.002
  7. Currie, I.G. (2003), Fundamental Mechanics of Fluids, (3th Ed.), CRC Press, Boca Raton, Florida, USA.
  8. Derickson, R.G. and Peterka, J.A. (2004), "Development of a powerful hybrid tool for evaluating wind power in complex terrain: atmospheric numerical models and wind tunnels", Proceedings of the 23rd ASME Wind Energy Symposium, Reno, Nevada, USA, January.
  9. Hu, F.Q., Chen, A.R. and Wang D.L. (2006), "Experimental study of wind field in bridge site located in mountainous area", J. Tongji Univ. Natural Sci., 34(6), 721-725 (in Chinese).
  10. Hu, P., Li, Y.L. and Liao, H.L. (2012), "Appropriate shape of boundary transition section of terrain model for mountains-gorge bridge site", Proceedings of the 7th International Colloquium on Bluff Body Aerodynamics and Applications, Shanghai, China, September.
  11. Hui, M.C.H., Larsen, A. and Xiang, H.F. (2009), "Wind turbulence characteristics study at the Stonecutters Bridge site: Part I-Mean wind and turbulence intensities", J. Wind Eng. Ind. Aerod., 97(1), 22-36. https://doi.org/10.1016/j.jweia.2008.11.002
  12. Hunt, J.C.R., Leibovich, S. and Richards, K.J. (1988), "Turbulent shear flow over low hills", Q. J. Roy. Meteorol. Soc., 114(484), 1435-1470. https://doi.org/10.1002/qj.49711448405
  13. Iizuka, S. and Kondo, H. (2004), "Performance of various sub-grid scale models in large-eddy simulations of turbulent flow over complex terrain", Atmos. Environ., 38(40), 7083-7091. https://doi.org/10.1016/j.atmosenv.2003.12.050
  14. Jackson, P.S. and Hunt, J.C.R. (1975), "Turbulent wind flow over a low hill", Q. J. Roy. Meteorol. Soc., 101(430), 929-955. https://doi.org/10.1002/qj.49710143015
  15. Kim, H.G., Patel, V.C. and Lee C.M. (2000), "Numerical simulation of wind flow over hilly terrain", J. Wind Eng. Ind. Aerod., 87(1), 45-60. https://doi.org/10.1016/S0167-6105(00)00014-3
  16. Kondo, K., Tsuchiya, M. and Sanada, S. (2002), "Evaluation of effect of micro-topography on design wind velocity", J. Wind Eng. Ind. Aerod., 90(12-15), 1707-1718. https://doi.org/10.1016/S0167-6105(02)00281-7
  17. Kundu, P.K. and Cohen, I.M. (2008), Fluid Mechanics, (4th Ed.), Academic Press, Burlington, Massachusetts, USA.
  18. Li, C.G., Chen, Z.Q., Zhang, Z.T. and Cheung, J.C.K. (2010a), "Wind tunnel modeling of flow over mountainous valley terrain", Wind Struct., 13(3), 275-292. https://doi.org/10.12989/was.2010.13.3.275
  19. Li, L., Zhang, L.J., Zhang, N., Hu, F., Jiang, Y., Xuan, C.Y. and Jiang, W.M. (2010b), "Study on the micro-scale simulation of wind field over complex terrain by RAMS/FLUENT modeling system", Wind Struct., 13(6), 519-528. https://doi.org/10.12989/was.2010.13.6.519
  20. Loureiro, J.B.R., Alho, A.T.P. and Silva Freire, A.P. (2008), "The numerical computation of near-wall turbulent flow over a steep hill", J. Wind Eng. Ind. Aerod., 96(5), 540-561. https://doi.org/10.1016/j.jweia.2008.01.011
  21. Mason, P. and Sykes, R. (1979), "Flow over an isolated hill of moderate slope", Q. J. Roy. Meteorol. Soc., 105(444), 383-395. https://doi.org/10.1002/qj.49710544405
  22. Maurizi, A., Palma, J.M.L.M. and Castro F.A. (1998), "Numerical simulation of the atmospheric flow in a mountainous region of the North of Portugal", J. Wind Eng. Ind. Aerod., 74-76, 219-228. https://doi.org/10.1016/S0167-6105(98)00019-1
  23. Meroney, R.N. (1980), "Wind-tunnel simulation of the flow over hills and complex terrain", J. Wind Eng. Ind. Aerod., 5(3-4), 297-321. https://doi.org/10.1016/0167-6105(80)90039-2
  24. Neal, D., Stevenson, D.C. and Lindley, D. (1981), "A wind tunnel boundary-layer simulation of wind flow over complex terrain: Effect of terrain and model construction", Bound. Lay. Meteorol., 21(3), 271-293. https://doi.org/10.1007/BF00119274
  25. OriginLab Corporation. (2010), Origin Reference for Origin 8.5 SR1, Northampton, Massachusetts, USA.
  26. Tsang, C.F., Kwok, K.C.S., Hitchcock, P.A. and Hui, D.K.K. (2009), "Large eddy simulation and wind tunnel study of an uphill slope in a complex terrain", Wind Struct., 12(3), 219-237. https://doi.org/10.12989/was.2009.12.3.219

Cited by

  1. Numerical Simulation of Wind Fields at the Bridge Site in Mountain-Gorge Terrain Considering an Updated Curved Boundary Transition Section vol.31, pp.3, 2018, https://doi.org/10.1061/(ASCE)AS.1943-5525.0000830
  2. Wind tunnel test and numerical simulation of wind characteristics at a bridge site in mountainous terrain vol.20, pp.8, 2017, https://doi.org/10.1177/1369433216673377
  3. Investigation of the longitudinal wind power spectra at the gorge terrain vol.20, pp.11, 2017, https://doi.org/10.1177/1369433217693632
  4. Wind characteristics at bridge site in a deep-cutting gorge by wind tunnel test vol.160, 2017, https://doi.org/10.1016/j.jweia.2016.11.002
  5. Numerical simulations of the mean wind speeds and turbulence intensities over simplified gorges using the SST k-ω turbulence model vol.10, pp.1, 2016, https://doi.org/10.1080/19942060.2016.1169947
  6. Wind tunnel tests on the characteristics of wind fields over a simplified gorge vol.20, pp.10, 2017, https://doi.org/10.1177/1369433216680635
  7. Wind tunnel study of wind structure at a mountainous bridge location vol.23, pp.3, 2016, https://doi.org/10.12989/was.2016.23.3.191
  8. An efficient Cholesky decomposition and applications for the simulation of large-scale random wind velocity fields pp.2048-4011, 2018, https://doi.org/10.1177/1369433218810642
  9. Time-resolved aerodynamic loads on high-speed trains during running on a tunnel-bridge-tunnel infrastructure under crosswind vol.14, pp.1, 2020, https://doi.org/10.1080/19942060.2019.1705396
  10. Buffeting response of a free-standing bridge pylon in a trumpet-shaped mountain pass vol.30, pp.1, 2015, https://doi.org/10.12989/was.2020.30.1.085
  11. Experimental and Numerical Investigation of Wind Characteristics over Mountainous Valley Bridge Site Considering Improved Boundary Transition Sections vol.10, pp.3, 2020, https://doi.org/10.3390/app10030751
  12. Effects of Inhomogeneous Wind Fields on the Aerostatic Stability of a Long-Span Cable-Stayed Bridge Located in a Mountain-Gorge Terrain vol.33, pp.3, 2015, https://doi.org/10.1061/(asce)as.1943-5525.0001117
  13. Wind characteristics in the high-altitude difference at bridge site by wind tunnel tests vol.30, pp.6, 2015, https://doi.org/10.12989/was.2020.30.6.547
  14. Non-uniform wind environment in mountainous terrain and aerostatic stability of a bridge vol.30, pp.6, 2015, https://doi.org/10.12989/was.2020.30.6.649
  15. Exceedance Probability Assessment of Pedestrian Wind Environment Based on Multiscale Coupling Numerical Simulation vol.33, pp.4, 2015, https://doi.org/10.1061/(asce)as.1943-5525.0001126
  16. Wind characteristics and flutter performance of a long-span suspension bridge located in a deep-cutting gorge vol.233, pp.None, 2021, https://doi.org/10.1016/j.engstruct.2020.111841