Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-421-2

International Heat Transfer Conference 15
August, 10-15, 2014, Kyoto, Japan

On Heat Transfer in the Stabilization Zone of an Attached Methane Flame in Air Coflow

Get access (open in a dialog) DOI: 10.1615/IHTC15.cmb.009980
pages 1266-1279

Abstrakt

This work is part of continuous efforts dedicated to the understanding of the role of heat transfer in jet-flame stabilization. Previous experiments performed utilizing several burner materials had shown that the attachment height Ha (axial distance between the burner and the base of an attached flame) was significantly smaller over a pyrophyllite burner than over other materials. This had been attributed to the much lower thermal conductivity kburner of pyrophyllite, leading to higher lip temperature Tlip. By using another material with similarly low kburner, Macor®, the present study enlightens this issue. Whereas an identical Tlip is obtained for both Macor® and pyrophyllite cases, Ha obtained over Macor® is higher than over pyrophyllite, remaining close to that obtained over other materials with a higher kburner. The particular pyrophyllite behavior thus does not originate from modified heat transfer at burner but rather from reduced radical quenching. Measurements are also provided for the temperature in the flame stabilization zone immediately above the burner rim, over a large range of fuel injection velocities ufuel. The axial and radial evolution with ufuel of the peak temperature location is consistent with the ufuel-dependent regions previously identified in terms of Tlip and flame location. Eventually, a close link is established between Ha, heat transfer in the attachment zone and the reactive properties of the incoming reactants. This is achieved through oxidizer-side dilution with both argon and carbon dioxide in relative proportions that simultaneously lead to identical Ha, Tlip, adiabatic temperature and laminar burning velocity.