Accession Number:

AD1104534

Title:

Structure and Dynamics of Highly Turbulent, Interacting Flames

Descriptive Note:

Technical Report,01 Dec 2015,31 Aug 2019

Corporate Author:

PENNSYLVANIA STATE UNIVERSITY UNIVERSITY PARK United States

Personal Author(s):

Report Date:

2019-11-29

Pagination or Media Count:

48.0

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.

Subject Categories:

  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE