flækt

Fläkt is a Swedish term for a device that moves air, commonly for ventilation or cooling; it can also denote a light breeze or gust of wind produced by natural or external factors. In everyday language, fläkt refers to machines used to move air in buildings, vehicles, and equipment, as well as to the sensation of air movement.

The most common types are axial fans, where blades push air parallel to the axis, and centrifugal (radial) fans, where air is drawn in and expelled perpendicular to the axis via a scroll housing. Mixed-flow and specialty designs exist; blade curvature (forward-curved, backward-curved) influences efficiency and pressure, and fans may be single- or multi-stage. Motors can be AC or DC, and some units include adjustable-speed controls.

Performance is described by volumetric flow rate (m3/h or CFM) and static pressure; efficiency is affected by blade design, housing, and motor losses. Noise and vibrations are considerations in design and installation; maintenance includes cleaning dust, inspecting bearings, and replacing filters.

Applications include heating, ventilation, and air conditioning systems; cooling of electronics and appliances; industrial processes, dust collection, and data centers; horticulture and aquaculture. The choice of fan depends on required airflow, pressure, energy use, and environmental conditions.