Untersuchungen zur Realisierung von Corecatchern
Ensuring a reliable energysupply while at the same time following economical and ecological interests is one of the major challenges of modern energy politics. As CO2-emissions are held responsible for world wide climate changes international authorities demand reduction of those. Facing growing population numbers in many regions of the world and a rise in energy consumption as well, in the future energy sources with little to now CO2-emissions will become even more important. Nuclear power offers these advantages. Corecatchers are devices for containing a molten core after a severe accident within a nuclear power plant for a long period of time. The dissertation at hand deals with the design of corecatchers and their installation in future pressurised water reactors. Emphasis is on the investigation of corecatcher concepts under thermal and chemical loads. After showing the course, consequences and boundary conditions of a core melt in common nuclear plants, an overview of recent research projects in this field is given. Melt types which were employed in the experiments are characterised and a selection for the following calculations is made. Afterwards aspects from material science dealing with interaction between melts and solids in the core are presented. They form the basis of the succeeding analysis about heat conduction within corecatcher systems. Center point of this dissertation is the calculation of the development of heat profiles with regard to the planned construction dimensions. In the course of these calculations in a first step the stationary system is balanced and the main influencing parameters are identified. Consecutive steps employ finite element methods to evaluate convection influence in non-steady state. Expected maximum temperatures as well as long-term characteristics are analysed this way. In addition to the common concept of pouring water as a cooling liquid onto the melt surface, an alternative concept basing on cooling by radiation is presented and evaluated. A direct comparison of the two concepts ends this dissertation.
info:eu-repo/classification/ddc/620, Ingenieurwissenschaften, Leichtwasserreaktor, Kernschmelzen
Networked Digital Library of Theses and Dissertations
Publikationsserver der RWTH Aachen University