Comparing Model data with Sensor data
Imposing Initial Conditions from Sensors to the Model
Automatic Hydraulic Grade Adjustment
| Product(s): | OpenFlowsTM WaterSightTM |
| Version(s): | Various |
| Area: | Help and Documentation |
Accessing latest model results for any asset (Map dashboard)
In WaterSight the user can access the real time model results for any element by accessing the map page, and toggle on Hydraulic Model on the side panel, as shown below:
By default pipes will be colour coded by flow and junctions will be turned off, but user can turn them on clicking the visibility eye button near Junction on the side panel. The user can also click in any model element from the map to see model results for the most recent run, as well as change the modelled variable/parameter by changing the dropdowns located on the side panel.
It is important to mention that in the map dashboard only model results of the last successful hydraulic model run are displayed. The user can define under Administration >> Numerical Model, both the run frequency as well as the hindcast and forecast period. The model results displayed in the map page will then comprise the hindcast + forecast period defined by the admin user.
Accessing model results trough the sensors graphs (Network Monitoring dashboard)
The user can also directly check hydraulic model results directly through the sensor graphs under Network Monitoring dashboard, both in the overview page, sensor detail page or when using the comparison graphs. To see model results when navigating in the overview or sensor detail graphs, make sure to turn on Model result under the visibility setting located on the top of the graphs (see above).
Hydraulic model results will be displayed with a blue colour line and will show for any sensor which is also configured / added to the hydraulic model that was uploaded in the digital twin. More information here, under WaterGEMS Model setup section.
Interpreting Model Results
Why model results shown in the map page do not comprise the exact same period as those shown in the Network Monitoring graphs?
While in the Map dashboard only model results for the last model run are shown (and the period will depend on the hindcast and forecast period defined by the admin user under Admin >> Numerical model, as explained above), the model results shown in the sensor graphs under Network Monitoring are a combination of the several model runs for each day (which get saved and displayed here). As the hydraulic model might run several times each day (depending on the run frequency defined), for each day it is created a combined model series that joins the best periods (best fit between model and real measurements) of each of the individual model series that run for that day.
Interpreting Hindcast and Forecast
The modelled values (always represented with a blue line in the graphs) are driven by the hydraulic model calculations based on all the model configurations. The hindcast period (defined in the Admin >> Numerical Models) will define the start of the simulation run, while the forecast period (also defined in Admin >> Numerical Models) will define the end date of the model run. Figure below illustrates how the start and end date of the simulation is obtained.
Whenever a new simulation is triggered (Now), the simulation start and end times are determined as follows:
- A new Now* is defined by rounding the current Now down to the previous full hour.
- The simulation start time is calculated as Now* minus the hindcast period.
- The simulation end time is calculated as Now* plus the forecast period.
For example: if the current time is 9:30 AM, Now* will be set to 9:00 AM and the model start time might be 5:00 AM. For that 5:00 AM start, the model uses initial conditions taken from sensor measurements at that same timestamp (for example, tank levels, PRV settings, or pump status). From 5:00 AM onward, the blue modelled line shown on the graphs is produced by the hydraulic model’s forecast calculations. When the model is exported from WaterSight and opened in WaterGEMS using the same start date, the results will be very similar.
Note that when zone demand adjustments, smart meter adjustments, or HGL adjustments are activated in WaterSight (under Admin >> Numerical Models), these adjustments are applied across the entire simulation period rather than being limited to the initial condition at the simulation start time.
If the user prefers the model runs to use SCADA values as the initial conditions for the Now instant, the hindcast period should be set to zero. Also note that the sensor values used for model initial conditions come from the processed 15‑minute time series rather than the raw sensor data. The processed 15‑minute series includes some cleanup, which can reduce the influence of outliers on the model initial conditions and subsequently on all model results.
Finally, if sensor data from SCADA or other telemetry systems are unavailable, the hydraulic model will still execute, but instead of using real measurements for boundary conditions (for example, actual tank levels, actual zone flows, actual PRV settings, etc.), it will use the initial model values defined within the WaterGEMS model.
See Also