Ventilspidare

Ventilspidare is a term used in Swedish ventilation engineering to describe a type of air-distribution ductwork that branches from a central supply line into several smaller ducts in a radial, spider-like pattern. The concept is intended to provide even air distribution from a single plenum to multiple ceiling diffusers.

Description and construction

A ventilspidare typically comprises a central hub or plenum from which multiple branch ducts extend outward, resembling the legs of a spider. The branches may be straight or gently curved and often terminate in diffusers or additional ducts. Balancing dampers are commonly installed on individual branches to adjust flow and achieve uniform air delivery. Materials include galvanized steel, stainless steel, or aluminum, with the assembly welded, bolted, or formed as a single sheet-metal piece. The layout is usually radial or star-shaped to accommodate ceiling geometry and diffuser placement.

Applications and advantages

Ventilspidare is used in spaces that require multiple air outlets from a single supply point, such as offices, conference rooms, classrooms, and other commercial interiors. Advantages include improved uniformity of supply air, potential reductions in noise and velocity variations, and a more compact arrangement in ceilings with limited space.

Limitations and considerations

Fabrication and installation are more complex than simple trunk-and-branch layouts, and changes to the system may require re-balancing. The design demands careful planning to ensure proper branch lengths and damper settings. In English-language HVAC literature, similar concepts are sometimes referred to as spider ducts or spider manifolds.