Yi Su, Yifeng Chen, Chunjie Sui, Tianjiao bi, Wei Chen, Bin Zhang
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引用次数: 1
Abstract
As a high energy density hydrogen-rich carrier, ammonia (NH3) is a highly promising carbon-free fuel. The large-scale industrial application of NH3 is limited by its low reactivity and high nitrogen oxide (NOX) emission. In this work, the flame and emission characteristics of ammonia/methane (NH3/CH4) non-premixed combustion were investigated under ultrasonic excitation. An experimental system was designed and built, including non-premixed combustion system, loading ultrasonic system, deflection tomography temperature measurement system and flue gas measurement system. Combustion and measurement experiments at different ultrasonic frequencies and NH3/CH4 blending ratios were carried out. Flame images and flue gas species concentrations under ultrasonic excitation were acquired. The 3D temperature field was reconstructed. The influence of ultrasonic excitation at different frequencies on flame characteristics, flame temperature field and emission characteristics of the combustion process was analysed. The mechanism of NH3/CH4 combustion enhancement and emission reduction was revealed when the flame was excited by ultrasonic waves. Results showed that part of the hydrocarbon fuels was replaced by NH3 to reduce carbon dioxide (CO2) emission. The height and colour of the NH3/CH4 flame were changed and the high-temperature area of the flame gradually expanded as ultrasonic acted on the flame. As ultrasonic frequency increased, the emission concentrations of unburned CH4, unburned NH3 and NO decreased significantly. The flame was excited by ultrasonic waves, which reduced its local equivalent ratio, improved combustion efficiency and suppressed NOX generation.
期刊介绍:
The main aims of Thermal Science
to publish papers giving results of the fundamental and applied research in different, but closely connected fields:
fluid mechanics (mainly turbulent flows), heat transfer, mass transfer, combustion and chemical processes
in single, and specifically in multi-phase and multi-component flows
in high-temperature chemically reacting flows
processes present in thermal engineering, energy generating or consuming equipment, process and chemical engineering equipment and devices, ecological engineering,
The important characteristic of the journal is the orientation to the fundamental results of the investigations of different physical and chemical processes, always jointly present in real conditions, and their mutual influence. To publish papers written by experts from different fields: mechanical engineering, chemical engineering, fluid dynamics, thermodynamics and related fields. To inform international scientific community about the recent, and most prominent fundamental results achieved in the South-East European region, and particularly in Serbia, and - vice versa - to inform the scientific community from South-East European Region about recent fundamental and applied scientific achievements in developed countries, serving as a basis for technology development. To achieve international standards of the published papers, by the engagement of experts from different countries in the International Advisory board.