Influence and modelling of urban runoff on the peak flows in rivers.
Surface waters and urban drainage systems are usually studied separately. However there are important interactions between both systems. Urban drainage systems can have an important impact on the surface waters, mainly at combined sewer overflows. On the other hand during periods of high water levels in a river, the runoff from the urban drainage system can be significantly influenced by backwater, which increases the probability of flooding in is not obvious, because the modelling tools for both systems are often hard to combine properly. To properly assess the probability of flooding for this kind of integrated water systems, different submodels are needed for both subsystems. In practice often one single model is used to describe the runoff to rivers despite the presence of urban catchments. The main objective of this study is to show the limits of this simplified approach. Furthermore, it is necessary to use continuous long term simulations, because of the differences in runoff behaviour. Detailed hydrodynamic models do not really fit for this purpose because of long simulation times and high demands in memory and disk space. Therefore simplified conceptual models are more useful.
Hydraulic Modelling of the Two-directional Interaction between Sewer and River Systems
Sewer networks and river systems are most often studied in a separate way. However, these systems may interact in two directions. Firstly, the effluents of urban drainage systems and combined sewer overflows have an impact on the receiving river. Secondly, a high water level in the river may avoid excess sewer flow to be discharged into the river. When one wants to model both directions of this interaction, multiple iterations have to be made using the one-directionally linked sewer and river models. A better solution is to integrate the numerical schemes of both models into a single model. The SOBEK software of WL I Delft Hydraulics makes this possible. In the study SOBEK was used to link existing models (after conversion from InfoWorks and Mike Ii) for the sewer network of Erpe-Mere and its receiving Molenbeek river. It is shown that for the simulation results along the river for both historical and synthetic rainfall events, the two directional linking generates similar results in comparison with the one-directional linking. However, for the results of the sewer model large differences are found under high flow conditions. Hence, the case--study illustrates that two-directional sewer-river interactions can largely influence sewer flood risk estimations and consequently also affect sewer system design.
Research on automatic tracking solar power system
The paper elaborates the features of solar power. On the foundation of it, it analyses the composing, the theory and the features of solar power system of automatic tracking, analyzing the function of mental composing and the important technology, making a compartment of the amount of generation of solar power system of automatic tracking and that of common solar power system.