Product(s): |
WaterSight |
Version(s): |
10.00. |
Area: |
Documentation |
Calibrating demands: Demand & Patterns (Zone-by-zone)
If you don't have a calibrated model, WaterSight can automatically calibrate your model demands. If the Zone demand adjustment option (inside the administration) is selected, WaterSight will automatically compute a pattern for each zone based on the real zone flow and will automatically apply it to the nodes belonging to the respective zone.
The zone pattern is automatically calculated by the software and always updated in real time, as summarized below:
- Step 1 - Each zone flow corresponds to the sum of all inflows, subtracted by all outflows, and by taking into account also the storage variation inside the zone;
- Step 2 - Last month of historical zone flow data is used to calculate a pattern for each zone (dimensional values), together with machine learning algorithm and advanced data analytics methods
- Step 3 - Each zone pattern, including forecast, is calculated using a machine learning algorithm, together with advanced data analytics methods. Bad data, including outliers and spikes are removed from the analysis and a different pattern for week days and weekends is computed;
- Step 4 - Each zone pattern with dimensional values is transformed into a zone multiplier (or dimensionless pattern) and applied to all the nodes that belong to the respective zone;
The zone dimensionless pattern (zone demand multiplier) covers all simulation window period defined by the user in the Numerical model settings (hindcast + forecast). The zone dimensionless pattern also differentiates between weekday, Saturday and Sunday. For example if the simulation window covers a Friday and a Saturday, the zone demand multiplier will include both days and Friday and Saturday will be quite different.
Another important aspect to mention is that zones pattern are continuously and automatically being updated in real time (whenever new data arrives into WaterSight) using always last month of historical data. This means that the zone pattern for today is slightly different than the zone pattern of the previous day and will be slightly different from tomorrow pattern. This is particularly useful when there are significant changes in zone demands such as winter and summer, or when zones boundaries are changed. In these cases also a new pattern is automatically obtained and multiplied to each of the nodes, without any user intervention.
The user can analyze each zone dimensional pattern automatically calculated by WaterSight by acceding to the Zone details graph (under Network Monitoring page). Once in the zone detail graph, the user should change the interval to "15 min" and the pattern dropdown option to "Last month" and enable the legend by clicking on the existent button on the top right of the graph.
Then disable on the graph all pattern confidence bands (5/95 band and 20/80 band) and the real time series, and keep only the median series (P50 Average). This is the dimensional pattern that will be automatically transformed into a dimensionless pattern (zone demand multiplier) used to multiply all existent node demands of the hydraulic model, in case this option is enabled in the Numerical Model settings. The user also has the option to export the zone dimensional patterns to CSV by clicking in the Download button located on the top right of the graph
To check and confirm that the model accuracy improved, the user should go to the Current Simulation page and click in any sensor icon (represented by a wi-fi symbol). Sensors icons highlight that a specific hydraulic element has a valid sensor signal associated to it, and therefore model and measured results can be compared. Below an example where a PRV modeled flow (at blue) is compared with the measured flow from SCADA, at green (with the zone demand adjustment option enabled).
If you want to compare this new result with the status quo condition (with no demand adjustments calculated by WaterSight, this means using the exact same configurations defined in the WaterGEMS model) please go to the Numerical Model settings (inside the administration) and set the demand adjustment option to "No update".
Then wait for the next model run, and accede to the same model element by clicking in the wi-fi symbol. Compare again model and simulated results.
Exporting WaterSight patterns for further analysis
Besides this, it is also possible to export and further analyze the dimensionless pattern generated by WaterSight. Please go to Realtime Simulation page > Previous Simulations and download the latest simulation.
Then open the sqlite file in WaterGEMS, go to Components > Patterns. Patterns automatically generated by WaterSight are automatically exported and can be analyzed in WaterGEMS. Pattern names are automatically generated based on the zone names in WaterSight.
Note: The pattern automatically generated in WaterSight and exported to WaterGEMS comprises the all simulation period defined in WaterSight (which can be more or less than 24 hours). Because week day and weekend patterns generated by WaterSight can be significantly different, in case the simulation period comprises a Friday and Saturday for example, two different patterns (for weekday and weekend) are combined into a single one automatically. Also note that in WaterGEMS it is required the starting multiplier of the pattern to be exactly the same value as the last multiplier, therefore this additional and last value is added only when exporting to the WaterGEMS file, but it is not being considered in the WaterSight simulations.
Additional and more refined analysis can be further done by the user. If for example some zones have some large customers which the pattern is well known, the user can create these large customer patterns in WaterGEMS and assign them specifically to those large consumers, being all other nodes with the zone patterns generated by WaterSight. Then upload that WaterGEMS model again into WaterSight, and make sure that now the "No Update" demand adjustment option is disabled (in the Numerical Model settings, inside the administration) so that the patterns that are in WaterGEMS are now considered.
For more information about patterns or forecasts, please click here.
For more information about WaterSight, please go to OpenFlows WaterSight TechNotes and FAQ's.