The team will commence field test data processing at this stage. All the field test data will be organized into one database for easy reference and retrieval.
Data Analysis
Flow and demand analysis will be carried out with the data available to determine the appropriate assignment of demand into the model for calibration. Head check for all the pressure points across the system is necessary to ensure any anomaly can be spotted and resolved before model calibration.
Leakage Detection Runs
The data retrieve from the field test enable the uncalibrated model to simulate for leakage detection. This will follow by roughness and demand pattern adjustment for calibration.
Model Calibration
Model calibration begins after the data analysis process. It is very important for the client to understand and agree with the general calibration approach adopted by the team to achieve calibration tolerance for various model factors.
Calibration criteria for the DMA model are as below:-
i. 24 hour profile of flow, pressure and level.
ii. Pressure within 1m tolerance at various nodes in the model. Calibration nodes will cover area within the DMA.
iii. Flow tolerance at all strategic point measuring the demand of the system is set within 5%. This is due to most of the DMA are multiple source fed which is harder to calibrate.
iv. Modelling actual operation of all control valves, i.e. Pressure Reducing Valve (PRV) or Flow Control Valve (FCV). Pressure tolerance 1.5m.
Issues such as initial roughness factor of the pipe, extent of valve throttling, limit of roughness increment and application of fixes and transfer nodes within the model are to be discussed and agreed with the client, making sure the model produced will meet their ultimate expectations and requirements.
During calibration, it is hoped that MWA will have representative to assist the team in resolving any anomalous result. Any anomalies which require further operational field work will be documented for the client own further action. The team will help to provide details and advice in this aspect. It is not possible for the team to resolve each and every anomaly as this is not feasible within the project timeline.