Smoke extraction system at a tunnel roof, to extract smoke from a fire by suction in an eddy hood structure, has an angled apron flanking the suction opening(s) to direct the rising smoke into them

摘要

The suction system (1) to extract smoke from a fire in a long passage, e.g. a tunnel (2), is especially an eddy hood smoke extractor with at least one suction opening (12,13) at the roof (5) along the tunnel length. The suction openings are flanked by an apron (17), with a length which is a multiple of the opening width, pitched at an angle from the longitudinal axis of the extractor to guide the rising smoke into the suction opening(s).