Transient Modeling of a Full-Scale Distribution System: Comparison with Field Data

The usefulness of transient models depends on their predictive ability. Consequently, their results should ideally be validated with field data. Despite numerous theoretical developments in the area of surge analysis, comparisons between field and modeled data for large distribution systems (DSs) are scarce. Transient low-pressure events at a water treatment plant (WTP) resulted in negative pressures at numerous locations in the DS. Three distinct surge events were measured in a full-scale DS and modeled with transient analysis software. The simulated pressure profiles were compared with field data collected from 9–12 sites within the DS. The objective was to apply a commercial transient analysis algorithm to a large and detailed network model (≈15,000 nodes/pipes) to estimate transient pressure variations within the network. Results showed similar trends for the three low-pressure events analyzed: the modeled pressures matched reasonably well with the measured pressures, as long as they remained positive. Whenever the pressures reached negative values, the simulated amplitude was larger than that of the recorded pressures. Modeling parameters and factors that might explain such results were tentatively investigated. The importance of field data in understanding and confirming the model outputs is highlighted.