- Neither branch is regulated - no configuration is required as there are no orders;
- One branch is regulated; or
- Both branches are regulated.
| Info | ||
|---|---|---|
| ||
| Note: The confluence node adds the upstream minimum and maximum constraints together. |
Unregulated branches
For rules based ordering, the confluence forecast model ignores any upstream nodes on the unregulated branch. This means that any upstream inflow node forecast models are ignored in the confluence node forecast calculation in rules based ordering phase. For network LP ordering, the unregulated branch may be configured as regulated if processes on the unregulated branch are to be modelled in the order phase.
One regulated branch
If there is only one regulated branch, the unregulated branch behaves like an inflow node. As there is only one regulated upstream branch, priority setting is not required. In this case, the confluence node can be thought of as acting in a similar manner to an inflow node.
As such, the branch which is unregulated needs to have forecasting ability of the inflow arriving, so that orders may be adjusted for the expected inflow. Therefore the confluence node has a forecasting model attached to it (as shown in Figure 1). The forecast model is the same as that available for an inflow node (see Forecasting inflows).
| Warning |
|---|
| Warning: The Inflow forecast should not forecast from the current time-step. |
Figure 1. Confluence node (Single regulated branch)
Both regulated branches
If both branches are regulated, you need to define how orders may be split by choosing one of the two methods specified under Regulated Ordering Methodology:
- Constraint based (default) - Specify a priority for each branch. Click the cell in the Priority column and edit the value; or
- Harmony based - As shown in Figure 2, you must define how the upstream storage volume for each branch is determined using the Function Editor (in the Branch Setup table). You ou must also specify how to split the upstream orders (under Harmony Ordering Setup) - using either:
- A function that Function that defines the proportion of the total order assigned to the named upstream branch based on model parameters; or
- A table that Table that has the proportional relationship on how orders are to be split upstream based upon the defined volume of water up each branch for each owner. The next section describes how to work with this table.
- If you select this option, you must also define how the upstream storage volume for each branch is determined using the Function Editor (in the Branch Setup table). Use the table as follows:
- To add a column, right click on one of the column headings and choose Add Volume. The other menu options will change the columns as shown in Figure 2; and
- To add a row, click on a cell in the last row to highlight and edit it. Input a value and press Enter.
- If you select this option, you must also define how the upstream storage volume for each branch is determined using the Function Editor (in the Branch Setup table). Use the table as follows:
| Info | ||
|---|---|---|
| ||
| Note: You may have to select the regulated link and then re-select the unregulated link before the forecasting controls become visible. |
Figure 2. Confluence node, harmony based