Aw. Pacek et Aw. Nienow, MEASUREMENT OF DROP SIZE DISTRIBUTION IN CONCENTRATED LIQUID-LIQUID DISPERSIONS - VIDEO AND CAPILLARY TECHNIQUES, Chemical engineering research & design, 73(A5), 1995, pp. 512-518
Distributions in a concentrated dispersion have been measured in a sti
rred vessel. With the capillary technique, with a wide distribution, e
ven after extensive testing of different sized capillaries and entry c
onditions and of threshold levels, both ends of the distribution were
cut off. Sampling time is a problem when studying fast transients, as
is the amount of fluid withdrawn when investigating phase inversion. P
rovided pictures can be taken, the video technique allows droplets fro
m 25 mu m upwards at concentrations up to those which cause phase inve
rsion, i.e. similar to 70% by volume dispersed phase, to be observed.
These observations can be made at the wall and, by means of a 7 mm dia
meter 'light pipe' and similar sized optical fibre strobe, inside the
vessel. With a framing rate of 50 per second, the technique gives, sec
ond-by-second, size distributions to any discretization and means to a
ny base. The structure is also revealed; for example, droplets-in-drop
s and bubbles are distinguishable from drops.