Center Push-Pull Ventilation For Open Surface Tanks.
A center push/pull ventilation system designed for use with open surface tanks was described. A full scale tank with a push/pull system consisting of a jet of air that moved air toward exhaust hoods on two parallel sides of the tank was constructed. Push/pull match points for the system were determined using smoke and a vane anemometer. Velocity profiles were constructed and general airflow patterns of the system were characterized using velocity and smoke tubes. Match points of the ventilation system were linear for push flows of 45 cubic feet per minute or higher. Velocity profiles showed that velocities in front of the hood diminished rapidly with distance from the hood face. Ambient velocity was achieved within 6 inches of the hood face. Air patterns showed that the air jet turned and climbed as it reached the hood face. At the hood slot, air turned and entered the hood. Most of the air entering the slot was jet and entrained air, the rest being ambient air from above the hood. The author concludes that these results will be useful for making close estimate designs for tanks with similar parameters.
NIOSH-Author; Task-performance; Industrial-ventilation; Ventilation-systems; Industrial-engineering; Air-flow; Smoke-control; Exhaust-hoods; Exhaust-systems; Equipment-design;
NTIS Accession No.
Division of Physical Sciences and Engineering, NIOSH, U.S. Department of Health and Human Services, Cincinnati, Ohio, 30 pages, 11 references