Uncertainty evaluation of multi-sensor flow measurement in a sewer system using Monte Carlo method

Abstract

Technical and economical impacts of flow measurements in sewer systems are a major concern in today’s system’s management. Thus, the quality of the measurements is considered to be a critical issue. Considering the complex nature of the measurand and the metrological requirements of local installations, the best available level of accuracy in measurement results should be sought. Therefore, both the knowledge of the measurand estimates and measurement of uncertainties are required for achieving robust results. Within this context, the quality of measurement results depends on the knowledge of the uncertainty contributions and on the selection of an appropriate method to evaluate the measurement uncertainty. The study of these aspects can be of major importance in providing information to management of the system, namely in upgrading and maintenance activities. This paper discusses the advantages of using Monte Carlo method to perform the evaluation of the measurement uncertainty, considering the non-linear and multi-stage nature of the mathematical models adopted. The influence of geometric conditions and other relevant parameters are considered in the quality of measurements. The study was developed in the context of a specific sewer system, using a particular measurement system, from which measurement data was gathered.