Transient Loading of Cyclone Separators on Use in Blowdown Systems. On use of cyclone separators for phase separation in blowdown systems, pressure-discharge systems, and flaring units, considerable momentary liquid forces are often encountered. Only few details are known about the transient loading and dimensioning of such systems. Thus the behaviour of the entering surge of liquid and its effect on cyclone separators has now been studied experimentally and theoretically. Water/glycerol mixtures of various viscosities were used in these model experiments. After entering the separator the liquid immediately forms a compact wall film. It rapidly expands sideways under the action of the centrifugal force and simultaneously decelerates. A two-dimensional planar mathematical model serves for stepwise calculation of the experimental results with regard to film extension, deceleration, and the resulting transient forces. The results are summarised in the form of design criteria.