Introducing Water Quality
Step-by-step:
In InfoWater Pro, Water Quality Modeling allows you to perform different types of quality analyses, each with specific options that you can set before running a simulation.
InfoWater Pro runs water quality analyses in conjunction with hydraulic simulations as part of the standard simulation. As with other simulations, the results of water quality analyses can be viewed as reports or graphs.
To access the Water Quality settings:
- From the Model Explorer, Operation tab, double-click the Simulation Options node.
- In the Simulation Options dialog, click the Quality tab.
Fields become available for editing depending on the analysis selection.
Note: For best results, when you are setting up any of these water quality options, it is recommended that the Quality Timestep should be set at 1/10th of the hydraulic timestep or smaller.
The different types of water quality models include:
- Chemical/Temp: Trace the water temperature or trace the movement of a reactive or non-reactive substance, such as chlorine, nitrates, sodium, or fluoride.
- Water Age: Calculates the water age over time in an extended period simulation analysis.
- Source Trace: Tracks the percentage of water reaching any node in the network that had its origin at a particular node over time; primarily, source nodes are tanks or reservoirs.
- Multi-Trace: Multiple source tracing batch process tracks the percentage of water reaching any node in the network that had its origin at a particular set of nodes over time.
- Advanced: This method is used to select a Multi-Species model and requires an additional license to run.
Depending on the node on which you want to run a water quality simulation, there are other options you can set. These are found in the Model Explorer Tools drop-down:
- System Reaction (for pipes and tanks): Defines the way in which a system reacts with chemicals and propagates them. Tank mixing controls the water quality leaving a tank.
- Bulk Coefficients: reflect the rate at which a chemical grows or decays due to reactions in the bulk flow of water over time.
- Wall Coefficients: reflect the rate at which a chemical decays due to reactions with the pipe walls over time.
- Initial Water Quality: Allows source concentrations and initial conditions to be defined.
- Quality Source: Allows source concentrations to be defined. In addition, three other types of boosters are available:
- Mass Booster: adds a fixed mass flow to that entering the node from other points in the network.
- Flow Paced Booster: adds a fixed concentration to that resulting from the mixing of all inflow to the node from other points in the network.
- Setpoint Booster: fixes the concentration of any flow leaving the node (as long as the concentration resulting from all inflow to the node is below the setpoint).
- Tank Mixing: Select a tank mixing method for the simulation.
- Complete: All water that enters a tank is instantaneously and completely mixed with the water already in the tank.
- 2-Compartment: The available storage volume in a tank is divided into two compartments, both of which are assumed completely mixed.
- First In First Out (FIFO): There is no mixing of water during its residence time in a tank. Water parcels move through the tank in a segregated fashion where the first parcel to enter is also the first to leave.
- Last in First Out (LIFO): There is no mixing of water during its residence time in a tank. The water stacks up; water enters and leaves the tank on the bottom.
IMPORTANT: Water quality simulations take a significant amount of time to reach a steady state condition, so you may set them to run for 3, 8, or even 12 weeks. In the result graph, you are looking for a steady repeating pattern once stability occurs.