Ammonia Measurements with Femtosecond Two-Photon Laser-Induced Fluorescence in Premixed NH₃/Air Flames

Abstract

Ammonia (NH3), which can be a hydrogen carrier, is a promising alternative to fossil fuels in the future carbon-free economy. In situ techniques feasible for the remote and non-intrusive detection of NH3 will provide strong support for developing clean NH3 combustion. Here, we demonstrated a femtosecond two-photon laser-induced fluorescence (fs-TPLIF) technique for interference-free in situ NH3 measurements in laminar premixed NH3/air flames. The two-head band of NH3 at ∼565 nm was observed, which verifies the feasibility of fs-TPLIF for NH3 measurements in a combustion environment. The single-shot NH3 fs-TPLIF images with efficient signal-to-noise ratios were obtained. The variation of the thickness of the reaction zone with the equivalence ratio of NH3 flames was also obtained. As a result of the broad line width of the femtosecond laser, the OH fluorescence was also observed together with the NH3 fluorescence. The potential of fs-TPLIF for simultaneous measurements of NH3 and OH with only one laser was analyzed. The laser power dependence of NH3 and NH emissions was investigated. The radial distributions of NH3, NH, and OH in the flame were also discussed. This work is the first attempt of fs-TPLIF for NH3 measurements in a combustion environment, and the results indicate that fs-TPLIF is a feasible tool for NH3 measurements in combustion diagnostics.

Second International Symposium on Biomass/Wastes Energy and Environment (BEE 2019), Tianjin, China, May 23–26, 2019

“…Received: January 6, 2020 Published: January 31, 2020 4 Novel Insights into Anaerobic Digestion of Rice Straw Using Combined Pretreatment with CaO and the Liquid Fraction of Digestate: Anaerobic Digestion Performance and Kinetic Analysis Zhao 5 Catalytic Pyrolysis of Herb Residues for the Preparation of Hydrogen-Rich Gas de Caprariis 6 Biomass Gasification: The Effect of the Surface Area of Different Materials on Tar Abatement Efficiency Chen 7 Hydrothermal Liquefaction of Sewage Sludge by Microwave Pretreatment Tao 8 Hydrogen Production via Aqueous-Phase Reforming of Ethylene Glycol over a Nickel−Iron Alloy Catalyst: Effect of Cobalt Addition Andrews 9 Anode-Boosted Electrolysis in Electrochemical Upgrading of Bio-oils and in the Production of H 2 Jin 10 Study on the Solubility between Diesel and Acetone− Butanol−Ethanol with or without Water Liu 11 Ammonia Measurements with Femtosecond Two-Photon Laser-Induced Fluorescence in Premixed NH 3 /Air Flames Ren 12 Modeling Study of the Impact of Blending N…”

“…The next entries in the table exemplify depolymerization processes that convert the renewable feedstock into more valuable streams, − including cleaner water . The last four entries explore characteristics of the fuels: their physical properties and their combustion. − …”