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Abstract: Recent observations show that the river Zenne (Belgium) remains well below the water quality goals stated by the European Union Water Framework Directive. An interuniversity, multidisciplinary research project was therefore launched to evaluate the effects of wastewater management plans on the ecological functioning of the river. To this end, different water quantity and quality processes had to be considered and modelled, e.g., the hydrology in the river basin, hydraulics in the river and sewers, erosion and sediment transport, faecal bacteria transport and decay. This paper considers the development of an Open Modelling Interface (OpenMI) based integrated model for the purpose of simulating the river's sediment dynamics. We used the Soil and Water Assessment Tool (SWAT) to model water and sediment fluxes from rural areas. The Storm Water Management Model (SWMM) was used to simulate the hydraulics of the river, canal, and sewer systems in urban catchments. New model codes for sediment transport and stream water temperature were developed to complement SWMM. The results show that the integrated sediment transport model reproduced the sediment concentrations in the river Zenne with ‘good’ to ‘satisfactory’ accuracy. We may therefore conclude that the OpenMI has been successfully implemented to integrate water quality models into a hydraulic one. While the OpenMI run-time data communication inflicted calculation time overhead, we found that the overhead was not significant with respect to the total run-time of the integrated model. [Copyright &y& Elsevier]

Abstract: During a storm in October 2002, wind induced ovalling vibrations were observed on several empty silos of a closely spaced group of eight by five thin-walled silos in the port of Antwerp (Belgium). To determine realistic dynamic wind loads and hence clarify the cause of the wind induced ovalling vibrations in the silo group, 2D URANS simulations are performed for seven angles of incidence between 0° and 90°. The emphasis in this paper is on the extensive verification and validation of the simulations to ascertain the accuracy of the numerical results. Subsequent analysis of the fluctuating wind pressures on the silo surfaces shows that ovalling oscillations of the eigenmodes with three and four circumferential wavelengths will be induced at the lee side of the silo group, corresponding to the lowest structural eigenfrequencies of the silos and the pattern of the visually detected vibrations during the 2002 storm. [Copyright &y& Elsevier]

Abstract: In this paper the flood problem of the river Demer, a river located in Belgium, is discussed. First a simplified model of the Demer basin is derived based on the conceptual reservoir modeling concept. This model was calibrated to simulations results with a more detailed full hydrodynamic model. Afterwards, the focus is shifted to a nonlinear model predictive controller (NMPC) which is based on a new semi-condensed optimization procedure combined with a line search approach. Finally, simulations are performed based on historical data in which the NMPC is compared with the current control strategy used by the local water administration. Uncertainties are added to the rainfall predictions in order to assess the robustness of the NMPC. [Copyright &y& Elsevier]

Results from a project in cooperation with the Belgian National Grid Operator ELIA are presented in this paper. Starting from a set of 245 time series, each one corresponding to four years of measurements from a HVLV substation, individual modeling using Periodic Time Series yields satisfactory results for short-term forecasting or simulation purposes. In addition, we use the stationarity properties of the estimated models to identify typical daily customer profiles. As each one of the 245 substations can be represented by its unique daily profile, it is possible to cluster the 245 profiles in order to obtain a segmentation of the original sample in different classes of customer profiles. This methodology provides a unified framework for the forecasting and clustering problems. [ABSTRACT FROM AUTHOR]