A statistical technique for comparing simulated and measured pressure surges

摘要

The effective design and operation of water distribution systems often requires detailed analysis of the pipeline hydraulics under dynamic (transient) conditions. The analytical models used to predict the pressure surges caused by such transient events are typically embedded in computer simulations which, due to the complexity of the code can vary widely in terms of robustness, ease of use, measurement uncertainty and so on. The designer is therefore faced with a difficult choice in deciding which is the most suitable code to use or, in the case of an in-house or preferred code, understanding what's its strengths and limitations are. A group of European companies and universities are, with the support of the European Commission, formulating ground rules for the effective design and operation of water and waste water pipelines under transient conditions. The work includes developing a method for benchmarking transient simulation software, part of which involves statistical techniques for determining the lack-of-fit between predicted and measured transient events. This dimensionless lack-of-fit parameter can then be used to obtain an aggregated lack-of-fit parameter for the performance of a software code on different transient operations.