An ancillary control object represents a flow control structure such as a weir or a pump. Ancillary controls are assumed to have zero length, and like a pipe, the ancillary control is defined as a link between two nodes.
The types of ancillary controls available in ICM are listed below:
The different types of ancillary control have different data requirements:
The following types of control link have different flow characteristics for the two directions of flow:
For these links it is important to define correctly which is the positive flow direction in the link.
All other controls are treated as hydraulically identical for both directions of flow. However, some controls should only be used with flow in one direction. It is up to you to ensure that reverse flow does not occur at these controls during simulation. The controls are:
The following types of ancillary objects are available in a SWMM network and each has different data requirements:
Ancillaries in ICM simulations for SWMM networks are calculated using the same methodology as SWMM5, which is described in the SWMM5 User Guide and the SWMM Reference Manual, Volume II, Hydraulics.