Interaction between flow structure and chemical reaction around the perforated gap of stainless steel–platinum catalytic partition reactor

• Published in: International journal of heat and mass transfer 2021-09, Vol.176, p.121418, Article 121418
• Main Authors: Li, Yueh-Heng, Peng, Kuan-Hsun, Kao, Hsiao-Hsuan
• Format: Article
• Language: English
• Subjects: Catalytic combustor; Catalytically-stabilized premixed flame; Channels; Chemical reactions; Combined stainless steel–platinum catalytic partition reactor; Combustion chambers; Combustion efficiency; Efficiency; Flame stabilization mechanism; Methane; Oxidation; Platinum; Premixed flames; Radicals; Species diffusion; Stabilization; Stainless steel; Stainless steels; Thermal energy; Velocity gradient
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2021.121418

•A stainless steel–platinum catalytic partition reactor was numerically investigated.•Two flame stabilization mechanisms were proposed to elucidate the flame behavior.•Interaction between flow structure and chemical reaction around percolated gap was studied.•Changing perforation location and dimension can improve the combustion efficiency. This study investigates the flow structure and chemical reaction around a perforation of a stainless steel–platinum catalytic partition reactor. The small-scale catalytic combustor was partitioned by the combined stainless steel–platinum plate into two channels. Hydrogen/air and methane/air mixtures were individually injected into each channel. The gap provided not only a low-velocity region to stabilize the catalytically-stabilized premixed flame but also a space to exchange the species and radicals diffusing or flowing from both channels, and this led to the inception of gas reaction. The simulation results of the flat catalyst combustor (FCC) and the flat catalytic combustor with a percolated gap (FCG) were compared; the methane/air combustion efficiency of the FCG was found to be much higher than that of the FCC. The reaction around the perforation provided thermal energy and sufficient oxidation radicals to sustain the methane/air flame in the upper channel and further influenced the combustion efficiency and combustion stabilization mechanism. The results indicated that the flame features of the hydrogen/air mixture in the lower channel would affect the flame stabilization mechanism and combustion efficiency of the methane/air mixture in the upper channel. This is due to the imbalance of the temperature and velocity gradients around the perforation.