Work

Experimental study on flame structure, stability, and emission characteristics of CH4-H2 swirl-induced inverse diffusion flame

Year: 2025

Type: article

Abstract: Inverse Diffusion Flame (IDF) is a flame with a central oxidizer jet surrounded by an annular fuel jet. In this study, a swirler was inserted into the oxidizer nozzle to increase the mixing intensity. The combustion and emission characteristics of the swirl-induced IDF (S-IDF) were investigated and compared with those of non-swirl IDF (N-IDF). The flame behavior, mixing, and radical distribution were visualized to compare the combustion characteristics of the S-IDFs and N-IDFs. The flame stabilities were evaluated by measuring the blow-out and the emission characteristics were examined by measuring the NOx and CO emissions. Although the S-IDF had 90% lower blow-out limits than N-IDF due to curtain effect induced by swirling radial flow near fuel nozzle, S-IDF showed cleaner emission performance by reducing the maximum 88% of CO emission. Here, hydrogen addition was suggested to enhance the operating range of S-IDF while maintaining clean emissions. The hydrogen-added S-IDF (50 vol.% of hydrogen addition) showed 7.5 times higher blow-out limits and 69% lower CO emission than methane S-IDF. Based on these findings, it was confirmed that S- IDF showed a cleaner emission performance by reducing CO emission, and inferior operation range can be supported by adding hydrogen as a fuel.

Source: Case Studies in Thermal Engineering

DOI: 10.1016/j.csite.2025.106342

Authors: Yuseon Jeon, Man Young Kim, Heejung Jung, Seungro Lee

Institutions: Jeonbuk National University, University of California, Riverside, Center for Environmental Research and Technology

Language: English

Topic: Combustion and flame dynamics

Subfield: Computational Mechanics

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: gold

Estimated APC paid: $1,620