Patent attributes
Systems and Apparatus for a personal ventilation system that provides a personalized column of clean air surrounding a user's space is presented. The personal ventilation system includes an air purifier with a fan and an annular gap downstream of the fan. The annular gap has an inner radius that is within 95% of the outer radius. The annular gap structure allows the air purifier to produce a column of air with an entrainment ratio lower than other commercially available fan. At a distance of 1.5 meters, the air purifier is configured to have an entrainment ratio of lower than 40%. The air purifier also has a removable filter located upstream of the fan. The ventilation system is capable of delivering highly-localized filtered air to a user or location.