Wadiso 6 User Guide > Optimization > Editing of Optimization Data > Water Demand Load Cases and Minimum Pressures

Up to 5 load cases (i.e. water demands and minimum pressures) for the optimization sizing of the pipes and pumps can be specified. This is done by selecting Optimization Data > Optimization Data in Model Tables > Loads/Pressures (Nodes).

The water demands and minimum pressures of the load cases are data associated with each node in the system. The Loads/Pressures (Nodes) menu option therefore gives access to the regular Node table, where other system data such as output can and should have been entered already.

When entering the Node table, the table scrolls to the column “Opt Demand Case 1 (L/s)”. There are 5 pairs of columns, to define the 5 load cases, labeled Opt Demand Case 1/ Opt Min Head 1 to Opt Demand Case 5/ Opt Min Head 5. The “Demand” columns are used to define the water demands at each node, and the "Head" columns the required minimum pressures at each node.

Initially by default, all 5 load cases are “inactive”, meaning that a 0 (zero) water demand is specified at all nodes, and a very large negative pressure (-IEIOm) is required at each node. A load case has to be activated by specifying an output and/or a proper pressure requirements at at least one of the nodes.

At least the first load case (Demand1/Head1) must be activated for optimization to take place. Load cases must be activated sequentially, as load cases may not be “skipped”. For instance, load case 3 may not be active while load case 2 is still in-active.

Since the "Load Case editor" is the same table as the Node table, it has the same special editing functions, sorting functions, customization possibilities and exporting facilities.

An easy way to initially activate and edit load cases is therefore to copy the values from the output column and paste it into a load case column. Thereafter use the ratio, fill and add functions to manipulate the values and finally do individual cell edits to define all the loads.

(The load case outputs and pressures are considered system specific data, which is saved as part of the system data.)

The load cases are properties associated with each node in the system data. Therefore, the water demands and minimum pressures Opt Demand Case 1/ Opt Min Head 1 to Opt Demand Case 5/ Opt Min Head 5 can also be edited directly in the Node table, or in the Node Info box available in the Albion environment, or by the selective editing features available in the Albion environment.