Required link-line attributes when integrating 1D river networks and 2D components

When setting up a link-line to integrate 1D river networks and 2D components, the required attribute fields are defined as follows:

• Type – Defines the calculation method for transferring water across the 1D-2D boundary. Options are Level Link (H), a Flow Link (Q) or a Weir Link (W). This must be the first field in your link line attribute table.

• Node1 – Node label of the 1D node associated to the start of a link line

• Node2 – Node label of the 1D node associated to the end of a link line

• Height1 – ground elevation at start point of link line. This can be a level from the surveyed cross section for Node1 or a level taken from an underlying ground grid (DTM). It can also be left unspecified by entering -9999 and the 2D model will set a level from its specified ground grid. This value is utilised in a 2D simulation to determine the head of water entering the 2D domain (in conjunction with 1D model water levels).

• Height2 – ground elevation at end point of link line. This can be a level from the surveyed cross section for Node1 or a level taken from the underlying ground grid (DTM). It can also be left unspecified by entering -9999 and the 2D model will set a level from its specified ground grid. This value is utilised in a 2D simulation to determine the head of water entering the 2D domain (in conjunction with 1D model water levels).

• Factora – Weir coefficient (optional field that applies only to weir type links). This can be set separately for all links in the 2D model simulation interface. The default value in this attribute field is 1.0, which will be assumed if this field is omitted from a link line.

• Factorb – Modular limit coefficient (optional field that applies only to weir type links). This can be set separately for all links in the 2D model simulation interface. The default value in this attribute field is 0, which will be assumed if this field is omitted from a link line.