Studying Effects
of High Intensity WindsWestern
Engineering researchers at the Boundary Layer Wind Tunnel Laboratory
(BLWTL) have recently received funding from Manitoba
Hydro, CEA and ICLR to study the effects of high intensity winds on transmission lines. This is Phase
2 of a project already in progress.
High intensity winds originate from
thunderstorms and essentially take two
forms:
(1) Downbursts, which are jets of cold and moist air impinging on
the ground surface and generating high speeds in the very vicinity
of the ground (below 50 meters), and
(2) Tornados, which are swirling surface jets of very small scale
(less than 100 m in diameter). Depending on the amount of swirl
generated, the flow in these tornados can take several forms. An
intense, very slim, vortex forms initially and breaks down aloft
into a larger, turbulent vortex. Finally, this turbulent vortex
touches down producing important damage.
In Phase 1 of this CRD program, two teams (one at Western and one at
the University of Surrey in UK) investigated the flow fields
resulting from these winds and applied them to transmission towers.
Phase 2 concerns the validation of the wind models and
implementation of the research in the design of transmission towers.
One of the essential components of Phase 2 is the construction of a
Tornado Simulator (or Tornado Vortex Chamber). The simulator
will be used to validate the numerical simulations from Phase 1 and
apply tornado wind loading on model scale structures.
"The Tornado Simulator is an innovative
component and will be the only one in Canada," says Dr. Horia Hangan,
Associate Professor and Associate Research Director, BLWTL.
"This project complements the exceptional experimental
infrastructure at the Boundary Layer Wind Tunnel Laboratory."