Air is passing through a bubble-cap plate at a superficial vapor velocity of 2 ft/s. Water is flowing across the tray at a rate of 0.1 ft3/(s)(ft diameter). The water and air are at a temperature of 70"F, and the pressure is 1 atm. Assuming stable operation of the plate and a liquid gradient of 0.4 in., estimate the percent of the total pressure drop across the tray due to the head of liquid above the slots. The following specifications apply to the unit:

Inside diameter = 6 ft

Minimum total cross-sectional area of riser, direction-reversal space in cap, or annular cap space = 15 percent of tower cross-sectional area

Total slot area = 10 percent of tower cross-sectional area

Length of chord weir = 0.7 X tower diameter

Slots in caps are triangular, and slot width at base = 0.4 in.

Slot height = 1.5 in.

Static submergence = 1.0 in