Numerical study on fuel-NO formation characteristics of ammonia-added methane fuel in laminar non-premixed flames with oxygen/carbon dioxide oxidizer

Energy ◽  
2021 ◽  
Vol 226 ◽  
pp. 120365
Author(s):  
Mino Woo ◽  
Byung Chul Choi
Author(s):  
Hongsheng Guo ◽  
Stuart W. Neill ◽  
Gregory J. Smallwood

The effect of water addition on NO formation in counterflow CH4/air premixed flames was investigated by numerical simulation. Detailed chemistry and complex thermal and transport properties were employed. The results show that the addition of water to a flame suppresses the formation of NO primarily due to the flame temperature drop. Among a lean, a stoichiometric and a rich premixed flame, the effectiveness of water addition is most significant for the stoichiometric flame and least for the rich flame, since the dominant NO formation mechanism varies. The addition of water also reduces the formation of NO in a flame because of chemical effect that increases the concentration of OH, while reduces the concentrations of O and H. Compared to the stoichiometric flame, the chemical effect is intensified in the lean and rich flames.


Author(s):  
Hongsheng Guo ◽  
W. Stuart Neill ◽  
Gregory J. Smallwood

The effect of water addition on NO formation in counterflow CH4/air premixed flames was investigated by numerical simulation. Detailed chemistry and complex thermal and transport properties were employed. The results show that the addition of water to a flame suppresses the formation of NO primarily due to flame temperature drop. Among a lean, a stoichiometric, and a rich premixed flame, the effectiveness of water addition is most significant for the stoichiometric flame and least for the rich flame. The addition of water also reduces the formation of NO in a flame because of the chemical effect. Compared to the stoichiometric flame, the chemical effect is intensified in the lean and rich flames.


1991 ◽  
Vol 83 (1-2) ◽  
pp. 155-173 ◽  
Author(s):  
Sherif H. El Tahry ◽  
Christopher Rutland ◽  
Joel Ferziger

2018 ◽  
Vol 22 (Suppl. 2) ◽  
pp. 769-776
Author(s):  
Fei Ren ◽  
Longkai Xiang ◽  
Huaqiang Chu ◽  
Weiwei Han

The reduction of nitrogen oxides in the high temperature flame is the key factor affecting the oxygen-enriched combustion performance. A numerical study using an OPPDIF code with detailed chemistry mechanism GRI 3.0 was carried out to focus on the effect of strain rate (25-130 s?1) and CO2 addition (0-0.59) on the oxidizer side on NO emission in CH4 / N2 / O2 counter-flow diffusion flame. The mole fraction profiles of flame structures, NO, NO2 and some selected radicals (H, O, OH) and the sensitivity of the dominant reactions contributing to NO formation in the counter-flow diffusion flames of CH4\/ N2 /O2 and CH4 / N2 / O2 / CO2 were obtained. The results indicated that the flame temperature and the amount of NO were reduced while the sensitivity of reactions to the prompt NO formation was gradually increased with the increasing strain rate. Furthermore, it is shown that with the increasing CO2 concentration in oxidizer, CO2 was directly involved in the reaction of NO consumption. The flame temperature and NO production were decreased dramatically and the mechanism of NO production was transformed from the thermal to prompt route.


Author(s):  
Usama J. Mizher ◽  
Peter A. Velmisov

Abstract. The search for new solutions in the field of energy, preventing negative impact on the environment, is one of the priority tasks for modern society. Natural gas occupies a stable position in the demand of the UES of Russia for fossil fuel. Biogas is a possible alternative fuel from organic waste. Biogas has an increased content of carbon dioxide, which affects the speed of flame propagation, and a lower content of methane, which reduces its heat of combustion. However, the combined combustion of natural gas and biogas, provided that the mixture of fuel and oxidizer is well mixed, can, on the one hand, reduce the maximum adiabatic temperature in the combustion chamber of power boilers at TPPs, and, on the other, increase the stability of biogas combustion. For the combined combustion of natural gas and biogas in operating power boilers, it is necessary to reconstruct the existing burners. For a high-quality reconstruction of burners capable of providing stable and low-toxic combustion of fuel, it is important to have theoretical data on the combustion effect of combustion of combinations of organic fuels on the temperature distribution in the combustion zone and on its maximum value. In this paper, self-similar solutions of the energy equation for axisymmetric motion of a liquid (gas) in a model of a viscous incompressible medium are obtained. Basing on them, a stationary temperature field in swirling jets is constructed. A set of programs based on the ANSYS Fluent software solver has been developed for modeling and researching of thermal and gas-dynamic processes in the combustion chamber. On the basis of the k - ϵ (realizable) turbulence model, the combustion process of a swirling fuel-air mixture is simulated. The results of an analytical and numerical study of the temperature and carbon dioxide distribution in the jet are presented.


2002 ◽  
Vol 29 (2) ◽  
pp. 1543-1550 ◽  
Author(s):  
Fengshan Liu ◽  
Hongsheng Guo ◽  
Gregory J. Smallwood ◽  
Ömer L. Gülder

Sign in / Sign up

Export Citation Format

Share Document