Pipe junction functionality is provided in Source to allow modelling of pumping water from one place to another. It can be used to model pumped water supply , bidirectional and bidirectional flows between storages and so onstorage's.
Scale
Model operates at the site scale and at any time step Source is capable of using (e.g. daily).
Principal developer
eWater Solution
Version
Source version 4.5
Dependencies
At least two Pipe Junctions are required in the network to define connections.
Availability
Automatically installed with Source.
Rule based ordering
In a rule based ordering system, for each pipe junction relationship, the expected pump volume can be defined through a function which should take into account any possible losses, such as evap loss, water travel lossevaporation and other transmission losses from channels. It is assumed to have no loss during that there are no losses during the pump process. The amount of water pumped out equals the amount of water pumped in. No time delay applies delays apply in pipe junction, the water pumped out gets to its destination within the same model time step.
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The volume of water pumped in the flow phase is calculated through a function which is also used in ordering the order phase and water user and constraint phase as the expected pump volume:
- Water User and Constraint Phase: the minimum and maximum constraints are affected by the expected pumping and whether it is incoming or outgoing,
- Order Phase: the orders will be affected (incoming water reduces water, outgoing water may generate an additional order),
- Flow Phase: moves the water in or out.
If the storage's upstream did do not release enough water to meet the expected pump requirement, or some released water gets loss on the way from storage to pipe sitethere are losses between the storage and the pipe junction, then the actual water that arrives at the pipe site junction is less than what the pipe site askedhas been requested, the pipe site junction would still pumped out its originally planned pump volume, such as pipe junction plans to pump the requested volume. E.g. If the Pipe Junction requests 100ML, but only 80ML gets to pipe junction, then pipe junction arrives, the Pipe Junction would still pump 100ML out, and the system will give an error to remind modeller indicating that there is a difference here, so modeller needs to consider more loss into between the requested and pumped volumes. The losses used in the pump flow function should be reviewed to account for this discrepancy.
NetLP
In NetLP system, Source works out an optimal way to pass water requirements and release water to meet these requirements at the lowest cost, so the expected pump volume will always be the same as actual pump volume. For each pipe junction relationship, pump capacity and pump cost are the key factors to that will affect flow direction in the whole system. Capacity determines the maximum pump capability that a pipe junction can pump out for that pump direction. Cost defines pump cost for each ML water pumped out from this pipe junction siteper ML. It can be quite sensitive for a certain cost range compared to costs of other water supply options.
Key assumptions
Assumptions:
- In rule based ordering system, the volume of pumped water is assumed to be the same as expected pump volume even there is shortfall. So it is important to take all possible losses into consideration when defining the expected pump volume.
- No loss and no time delay apply during pump process.
Input
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Data
Refer to the Source User Guide for detailed data requirements and formats.
Output
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Data
Outputs include the following results:
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