Bridge River and Seven Mile Arc Flash Ducting

Bridge River and Seven Mile Arc Flash Ducting

Client: BBA
Project Location: Bridge River, BC

EnFlux developed a novel 3D CFD model of an arc flash event within a transformer enclosure to determine pressure distribution, flow velocity through the exhaust ducting, and incident energies outside the exhaust of the enclosure where occasional human occupancy is expected. The flow, heat transfer, and radiation was modeled using ANSYS. The numerical model was used to verify the structural and ducting design of the enclosures for Bridge River Generating Station #2 (BR2) 13ET5&6 and Seven Mile excitation transformer units G1, G2, and G3 excitation transformer units. The model was validated using pressure testing and incident energy values calculated using ETAPs software. The results of the analysis were also used to provide an incident energy map where the enclosure ducting outlet was located to determine safe and danger zones for human occupancy. EnFlux Engineering Ltd. was the Engineer of Record for the FEA model developed and the design basis for ducting for the enclosure.

Highlights

= Novel 3D numerical modeling of arc flash event occuring inside a transformer enclosure (ANSYS was used to model the arc flash physics),
= Validation using test data as well as incident energies calculated using ETABS,
= Calculation of pressure distribution inside the enclosure and the exhaust ducting,
= Detailed design of the exhaust ducting, and
= Incident energy mapping at the outlet of the exhaust ducting to determine safe zones and restricted zones for human occupation.