Decreasing rain lowers the flow (Figure 3).
The water level in the chamber and the higher pipeline gradually falls below the top of the regulator. The loss of pressure causes the vortex to collapse. It is replaced by air, which, with some delay, is sucked into the regulator, which does not return to normal function until the water level is just below the level at which the formation of the attenuating vortex began (Figure 2).
The collapse of the vortex causes a sudden increase in the flow of water through the flow regulator, flushing out any upstream sediments along with it. See the typical peak of the characteristic in Figure 5.
In certain situations, the best solution is the centrifugal flow regulator (a different design in Mosbaek's range of regulators). In other words, where the need to control the flow involves small water volumes.
The centrifugal flow regulator's orifice opening is bigger than that of the cyclone flow regulator, and in this situation it lessens the risk of clogging, making the centrifugal regulator the most appropriate for this situation. There are two main types of centrifugal flow regulators: horizontal (used for waste water), and vertical (for rainwater). The design of the centrifugal flow regulator differs from that of the cyclone flow regulators, but it functions by the same principle.