=+11-3.

To ventilate a space, it is desired to discharge free isothermal jets vertically downward from a ceiling 24 ft (7.3 m) above the floor. The terminal velocity of the jets should be no more than 50 ft/min (0.25 m/s), 6 ft (1.83 m) above the floor. Determine a reasonable diameter and initial volume flow rate for each jet [D] < 12 in. (30 cm)].