When calibrating a hydraulic network model, the goal is to determine the best set of wall coefficients which produces the lowest overall deviation between the numerically simulated model results and the observed field data at user specified locations in the system. Observed field data consist of chemical concentration measurements.

Grouping of pipes is very useful when calibrating for pipe wall coefficients. Pipes must be grouped together based on their known physical characteristics such as material, date of installation, location, and diameter. It is assumed that all pipes within a group will have an identical wall coefficient.

WQ Calibrator casts the calibration problem as an implicit nonlinear optimization problem, subject to explicit inequality and equality constraints. It computes the optimal wall coefficient within user-specified bounds, such that the deviation between the model predictions and field measurements is minimized. The optimal network model calibration problem is thus governed by an objective function and its associated set of constraints.