Due to liquid head

Pressure drop due to liquid head above slots, sieve openings, or valve openings. 

PRESSURE DROP DUE TO LIQUID HEAD ABOVE SLOTS, SIEVE HOLES, OR VALVE OPENINGS. Reference to Fig. 16-10 shows that the total head above bubble-cap slots for an average cap is the sum of static submergence Sm, height of liquid crest above weir ha, and average liquid gradient 0.5hg. The same... 

EVALUATION OF TOTAL PRESSURE DROP PER TRAY. The total pressure drop of the gas across a bubble-cap tray as indicated by Fig. 16-10 equals the sum of the pressure drop through the cap assembly and the pressure drop due to liquid head above the slots, or... 

Estimate the gas pressure drop across the tray, the percent of this pressure drop due to liquid head above the top of the bubble-cap slots, and the liquid head in the downcomer. 

Percent of A pT due to liquid head (average) above top of plate... 

Where it is desired to maximize circulation rate or minimize boiling point elevation due to liquid head (e.g., heat-sensitive materials distilled under vacuum). 

P dropL = Pressue drop due to liquid head on stage (Bar). 

Pressure Drop Due to Liquid Head above Slots, The pressure drop due to the liquid head above the top of the slot is customarily taken as equal to the actual liquid depth above the slots. This liquid depth is frequently taken as weir height, A, plus the weir crest, her, minus the height of the top of the slot, A,p, thus... 

H is the depth of the heads. The vertical load on each head is given hy V = 2Hw/3 and is assumed to act at the center of gravity of the head. 1 hc horizontal pressure on the heads due to liquid heads is resisted by a horizontal force F acting as shown in Fig. l. 6b. It is interesting to note that for hemispherical heads where H is equal to r, the bending moment at the head-to-shell junction due to force F and vertical force V is zero. The bending moment at any point in the vessel is obtained from statics as shown in Fig. it>... 

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