The Dyson Air Multiplier from Dyson Inc., Chicago (www.dyson.com), represents the next step in fan design. But unlike traditional fans with their whirling blades and choppy airflow, this bladeless version sends a constant stream of cooling air. And there‘s no danger from kids of any age sticking their fingers into the blades.
The original model uses a 40-W electric motor to pull about 1 cu ft of air in and send it out through a small (1.33-mm) slit in the circular output assembly. The air flows over the assembly, which has an airfoil-shaped ramp to control the airflow’s direction. The moving air entrains nearby air to also travel through the assembly. In fact, about 14 times more air joins the airflow than the device‘s motor actually pushes through the assembly. The company sells the device for $300 to $450, depending on size.
