The Influence of Swirl Angle on the Irreversibilities in Turbulent Diffusion Flames

Abstract

The objective of this paper is to investigate the volumetric irreversibilities of turbulent swirling diffusion flames. The theoretical background of analysis relies on the local transport exergy equation, which allows the formulation of the well-known Gouy-Stodola theorem at the continuum level. It is already known that, in the case of turbulent flame, the chemical, thermal and mass diffusion irreversibilities represent in order of enumeration the predominant sources of exergy destruction. But these irreversibilities have a more complicated structure than in the laminar flames because the turbulent fluctuations generate new and important irreversibility sources, strongly influencing all the mechanisms mentioned above. Using numerical techniques for flow and multi-species balance equations, this paper tries to emphasize the role of both, swirling number and turbulent intensity field, not only in the burning process intensification but also in the irreversibility creation.

Keywords

• diffusion flames, numerical simulation, exergy destruction, entropy generation