ISBN 9783843913317

978-3-8439-1331-7, Reihe Energietechnik

Christian Schuhbauer
Dynamic and Coupled Simulation of the 700°C Coal-Fired Power Plant

190 Seiten, Dissertation Technische Universität München (2013), Softcover, A5

Zusammenfassung / Abstract

In this dissertation transient and detailed coupled simulations are performed for a coal-fired power plant with live steam parameters of 705 °C and 365 bar. The simulation tool used for the dynamic simulation is APROS. The overall model generated also includes, in addition to the steam generator, the turbine, the condenser and the preheater groups, a model for the mills as well as the necessary controls for temperature, pressure, feedwater, unit, start-up and shutdown. In addition to determining the power plant dynamics during operation under load and the primary reserves, start-ups and shutdowns are also simulated. To determine the life assessment of critical thick-walled components, a model, based on the DIN EN 12952 is implemented which makes it possible to calculate creep and fatigue damage online. In addition, a detailed model is developed to enable conclusions to be drawn concerning the influence of heating imbalances, fouling and mill malfunctions on the steam generation. Therefore the fire- and steamside are simulated separately. The steamside is again modeled in APROS, though here the above mentioned overall concept is increased from one to four strands. The fireside is calculated with a three-dimensional CFD simulation using ANSYS FLUENT. The two models are coupled with each other. The ANSYS FLUENT simulation thereby delivers the heat flow to the membrane walls and the tube bundles. These two parameters serve as a boundary condition for the APROS simulation. On the steamside the inner tube wall temperatures are calculated which in turn are used as boundary condition for the fireside simulation. The solution is therefore iteratively calculated. MATLAB is used as interface for submitting the boundary conditions between fire- and steamside.

The investigations show that the power plant dynamics are comparable with the state of the art of coal-fired power plants. The life assessment confirms that the newly developed nickel-based alloys are adapted for operation in the 700 °C power plant. In addition, the influences of heating imbalances, fouling and mill malfunction are effectively handled by the tangential firing in combination with the strand mixing on the steamside.