Fig. 7 Film and jet flow. (a) The front side; (b) The reverse side; (c)
Diagram of FJF.
Spray
liquid distribution has a larger spray density than that of the overflow
liquid distribution. Fig. 7 shows the flow pattern of FJF. The operating
conditions are L W = 156
m3/(m2*h), F s= 0.8 (m/s*(kg/m3)0.5). The liquid
phase sprays the plate unit surface through the tube-type liquid
distributor. Because of the dispersed distribution of the liquid
columns, most of the spray columns directly hit the surface of the unit
and then spread out to form an uneven liquid film, as shown in Fig. 7a.
Moreover, a small portion of the spray column hits the sieve area or
flows through the holes directly. Other columns hit the edge of the
holes, shearing into two parts. Columns with a larger vertical downward
velocity component efflux from the sieve holes, while the ones with a
larger horizontal velocity component gather on the liquid film on the
surface of unit and spread continuously. Because of the high density of
the liquid spray, the liquid film on the unit surface is thicker. With
the influence of gravity and the driving force of the gas phase, the
liquid phase on the sieve holes not hit with the spray columns will
gradually gather and flow in the form of liquid columns. Therefore,
there is a continuous outflow at each sieve hole on the back of the
unit. However, because of the low gas velocity, the liquid column is
less disturbed by the gas phase, and the boundary is clear, see Fig. 7b.
3.1.2.2. JMF