Thermal Analysis of Cable Sealing Ends
A general analytical method for thermal analysis of high-voltate oil-filled cable sealing ends is presented. Oil flow within the conductor oil duct, longitudinal heat flow through the conductor and conductor losses variation with temperature are taken into consideration. The method is successfully applied for a sealing end of a 300 kV, 2000 mm2 integral sheath cooled oil-filled cable. A companion paper where cable joints are analyzed, is referenced.
Electrothermal Analysis of Low- and Medium-voltage Cable Joints
Abstract In this article, an analytical method to calculate the steady-state temperature distribution along the joint of a three-phase distribution cable is presented. The results of this method are compared with those obtained by an experimental study and by the finite-element method. It is found that the results of the analytical method are in good agreement with those obtained by an experimental study and by the finite-element method. The effects of connector dimensions as well as the effect of the ambient temperature and cable load current on the maximum temperature of the joint are discussed in detail. From the present analysis, it is found that the increasing of the connector length is more effective than the connector thickness in the reduction of the maximum temperature of conductor inside the joint.
Impacts of climate and land use changes on flood risk management for the Schijn River, Belgium
Abstract Flooding is the most common natural disaster in Europe. Modern flood risk management relies not only infrastructure development but also on governmental and non-governmental actors applying legal, economic and communicative water management instruments. Within the European Union (EU), flood management closely relies on policy set at the EU and national levels. It is now recognized that a sound understanding of climate change is required in addition to current management by taking into account land use change and socio-political context, as climate and land use changes have major impacts on hydrological responses. This paper investigates the hydrological behavior due to urbanization under current and future climate scenarios of high summer and high winter rainfall for 20 sub-catchments of the Schijn River, located in the Flanders region near Antwerp, Belgium. As urbanization increases and existing rainfall-runoff models neglecting the specific behavior of urban runoff, a hydrological model was developed based on a basic reservoir concept and applied to the existing rainfall-runoff model (PDM) flow to examine the specific urban contribution. Results revealed that peak flow for urban runoff and the total peak flow (i.e. rural and urban runoff) were significantly higher (i.e. ranges from 200% to 500%) than the existing rainfall-runoff model (PDM) flows, because of faster and more peaked urban runoff response. The impact of climate change on current and future conditions was also assessed by estimating peak flows with respect to return periods from the flood frequency curve. The predicted peak flow of high summer future climate scenario was significantly higher (i.e. ranges from 200% to 250%) than that of the current climatic condition for this region. Furthermore, hourly peak flow and daily volume ratios of 100-year return period for the highest, lowest and average impervious area were projected for the time horizon of the year 2100. It is concluded that climate change impacts contribute the most in producing peak flow in coming years, while increased urbanization takes the second place for both hourly and daily values. Results on urbanization effect and climate change impact assessment are useful to the water managers for spatial planning, emergency planning and insurance industry.