Structure and Dynamics of Highly Turbulent, Interacting Flames

Abstract

The overall objective of this program was to develop a fundamental understanding of the structure and dynamics of highly turbulent, interacting flames. Flame interaction occurs in a wide range of combustion applications of interest to the Department of Defense, and as flame interaction can introduce additional flame physics to turbulent flames, it is an important addition to the research portfolio focusing on turbulent flame behavior. The key learnings from this program are: Implementation and publication of a methodology for rigorously identifying flame interaction events and their characteristics from high-speed PLIF images, Quantification of flame interaction event occurrence frequencies and how impactful these events are on the flame surface and its area, Identification of the role that the flow field plays in determining flame interaction statistics and topology, Differentiation of flame interaction statistics for different flame shapes, including Bunsen flames and V-flames, Quantification of the impact of pocket formation on flame area dynamics and flame speeds, Identification of the role of piloting on local flame dynamics and flame structure, Development of a method for estimating the influence of out-of-plane errors on planar flame measurements. The results of this study have several implications for the future of turbulent flame research. First, flame interactions affect a non-negligible amount of the flame surface of a turbulent flame and can result in significant losses and additions of flame area at any given time. However, many of these interactions are happening on length scales smaller than the Taylor microscale of the incoming turbulent flow, indicating that these interactions need to be accounted for at the sub-grid scale.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Nov 29, 2019
Accession Number
AD1104534

Entities

People

  • Jacqueline O'Connor

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Force Research Laboratories
  • Algorithms
  • Combustion
  • Equations
  • Flame Propagation
  • Flow Fields
  • Fluid Flow
  • Fluorescence
  • Image Registration
  • Laser Induced Fluorescence
  • Lasers
  • Rate Of Consumption
  • Rate Of Formation
  • Spatial Distribution
  • Three Dimensional
  • Turbulent Mixing
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Computational Fluid Dynamics (CFD)
  • Systems Analysis and Design