ISBN 9783843939300

978-3-8439-3930-0, Reihe Ingenieurwissenschaften

Arne Scholtissek
Flamelet Modeling in Composition Space for Premixed and Non-Premixed Combustion

198 Seiten, Dissertation Technische Universität Darmstadt (2018), Softcover, A5

Zusammenfassung / Abstract

Computational Fluid Dynamics simulations of technical combustion systems have to describe three overarching aspects of chemically reacting flows: turbulent flow, gas phase chemistry, and multiphase interactions. These aspects entail a multitude of phenomena and sub-processes which are commonly found in all types of combustors. This work deals with the second aspect: modeling the detailed gas phase chemistry based on the flamelet concept.

An advanced flamelet theory, applicable to both premixed and non-premixed combustion, is developed. Flamelet equations for the species mass fractions, the temperature, and the gradient of the conditioning variable are derived and solved directly in composition space. The equations are parametrized by the fundamental flame parameters strain and curvature. It is shown that the flamelet model captures important characteristics of premixed and non-premixed flames, such as detailed flame structures, extinction limits, and flame propagation speeds. Further, unstable flame configurations, such as negatively strained flames, can be studied utilizing the approach. Besides applications of the flamelet model to canonical combustion configurations, the work contains flamelet analyses for multi-dimensional flames revealing capabilities and challenges for flamelet modeling.

About the author:

Arne Scholtissek received his doctoral degree (Dr.-Ing.) from Technical University Darmstadt, Germany where he worked as a research associate at the institute for Simulation of reactive Thermo- Fluid Systems (STFS).