Wind and Structures

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Large-scale quasi-steady modelling of a downburst outflow using a slot jet

  • Lin, W.E. (Department of Mechanical & Materials Engineering, The University of Western Ontario) ;
  • Savory, E. (Department of Mechanical & Materials Engineering, The University of Western Ontario)
  • Received : 2006.06.22
  • Accepted : 2006.09.22
  • Published : 2006.12.25
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Abstract

This article synthesizes the literature on the meteorology, experimental simulation, and wind engineering ramifications of intense downburst outflows. A novel design of a large-scale test facility and experimental evidence of its validity are presented. A two-dimensional slot jet is used to simulate only the outflow region of a downburst. Profiles of mean velocity and turbulence quantities are acquired using hot-wire anemometry. Comparison with the literature provides empirical evidence that supports the current approach. A geometric analysis considers the validity of applying a two-dimensional approximation for downburst wind loading of structures. This analysis is applicable to power transmission lines in particular. The slot jet concept can be implemented in a large boundary layer wind tunnel to enable large-scale laboratory experiments of thunderstorm wind loads on structures.

Keywords

References

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