Local Exergy Losses of the Sandia Flame D: A Turbulent Piloted Methane–Air Jet Flame

Abstract

Exergy is a useful tool for quantifying the locations, types, and magnitudes of wastes and losses caused by unavoidable irreversibilities in real processes. However, for the typical and popular turbulent piloted non-premixed methane–air jet flame, the Sandia flame D, no detailed exergy losses have been reported. This study reports the local exergy losses of the Sandia flame D for the first time by demonstrating the local exergy losses from heat transfer, chemical reaction, gas diffusion, and viscous dissipation. The results show that the local exergy losses from heat transfer, chemical reaction, gas diffusion, and viscous dissipation are in the ranges of 0–23210.17, 0–10796.30, 0–6.79, and 0–3.39 kW/m³ in the computational domain, respectively. These make the total local exergy loss of the Sandia flame D vary in the range of 0–23282.45 kW/m³, and it is mainly contributed by heat transfer (71.42%) and chemical reaction (28.56%), followed by gas diffusion (0.01%) and viscous dissipation (0.01%). The results obtained from this study illustrate well what the local exergy losses of the Sandia flame D are as well as how they are caused and contributed.