Knappstein,Robert

Large Eddy Simulation of reacting coal particles in an Oxyfuel-environment

Introduction and Motivation

Carbon dioxide (CO2) is one of the gases, that contribute to the so called greenhouse gas effect. It is the aim of many countries – Germany among them – to reduce the emission of this gas.

The combustion of fuels, which takes place in fossil powerplants, is one of the major reasons for the increase of CO2 – concentration in the atmosphere. In order to ensure a reliable energy and electrical power supply, there is still the need for powerplants fired by fossil energy sources.

The oxyfuel-technology is an approach to avoid the emission of CO2 into the atmosphere. Because coal or gas is burned in an environment of O2 and recirculated flue gas, the combustion products are mainly H2O and CO2. The water can easily be separated by condensation, so that CO2 can be captured for storage or further use.

Method and Theory

This work focusses on the simulation of reacting coal particles in an oxyfuel-environment. The aim is to gain a fundamental understanding of turbulence-chemistry-interactions – especially with reference to heterogeneous reactions and a CO2 -rich environment – and to contribute to models and methods for a reliable description of particle transport, turbulence, gas phase combustion and particle combustion.

In this work, the concept of Large Eddy Simulation (LES) in combination with an Euler-Lagrange approach for the computation of the two-phase system is used.