Confluence¶

At a glance…¶

The confluence node can be used to merge flow pathways. The node is otherwise passive.

[node.walker_confluence]
type = confluence
loc = 20, 30
harmony_fraction = if(node.little_dam.level > 24.0, 1, 0)
ds_1 = my_other_node

Property	Description
[node.?] (compulsory)	Start of node declaration. This says we are creating a node, and also defines the name of the node. Node naming conventions are discussed at . Example: `[node.walker_confluence]`
type (compulsory)	The node type, which is “confluence” in this case. `type = confluence`
loc (compulsory)	The location of the node in cartesian coordinates. Example: `loc = 20, 30`
harmony_fraction (optional)	A dynamic expression that determines the fraction of orders directed up the first upstream link (that is, the first link to this node defined in the model file). Example: `harmony_fraction = if(sim.month > 6, 1, 0)`
ds_1 (optional)	Name of the downstream node. This property defines a downstream link. Inflow nodes may only have 1 downstream link. Example: `ds_1 = my_other_node`

Result	Description
dsflow	Downstream flow [ML]
usflow	Upstream flow [ML]
harmony_fraction	The harmony fraction value [proportion between 0 and 1]
ds_1	Downstream flow on link ds_1 [ML]
ds_1_order	Orders on the link ds_1 [ML]

All inflows are passed to the downstream node.
Propagation of orders is as follows:
The harmony_fraction is evaluated to determine the proportion of orders to be directed to the first upstream link (that is, the first link to this node defined in the model file).
The complementary proportion will be directed to the second upstream link.
If either upstream branch has a shorter lag time than the other, then the orders designated for the short branch will be delayed by the n timesteps (n = long_branch_lag - short_branch_lag) such that the water would be delivered on the correct timestep to meet downstream orders.
This node should not have more than 2 upstream links.

None.