Numerical Research On The Effect Of Turbulent Radiation Interaction On The Prediction Of Soot

Soot has an important impact on the environment,human health and the safe operation of aero-engine,accurately simulating the formation of soot and reducing the formation of soot are of great significance.Usually,the formation of soot is very sensitive to temperature,and radiation heat transfer is regarded as one of important factors affecting temperature.Based on the review of the research status of soot and turbulent radiation interaction at home and abroad,the impact of turbulent radiation interaction(TRI)on the formation of soot and the emission reduction of soot are studied in this paper.First,a high-precision method considering TRI and WSGG2013 non-gray radiation model is introduced to predict soot and temperature distribution in two-dimensional turbulent ethylene diffusion flame.Comparing with conventional methods,the results reveal that considering TRI and WSGG non-gray radiation characteristics,the predicted results of soot concentration and temperature show more satisfactory agreement with the experimental values.Moreover,more accurate results can be obtained with modifying model constant for soot inception rate.Then,the regulation and emission reduction of soot are studied,and the effects of turbulent radiation interaction on soot and temperature under different fuel dilution and oxidant concentration in oxygen-enriched combustion are analyzed.The results show that the volume fraction of soot is lower than the visible formation limit of e-9 when the volume concentration of ethylene is less than 50%,while the relative error of temperature due to ignoring TRI increases first and then decreases.Increasing the coflow oxygen concentration will result in decreasing of the distribution and concentration of soot.When the oxygen concentration adds up to 80%,the area of soot formation is very small,and the volume fraction is 2.78e-8.When the oxygen concentration is below 60%,the flame temperature will be over predicted without considering TRI.While the temperature will be lower without considering TRI with oxygen concentration no less than 60%.Finally,the simulated results of soot formation in the DLR dual-radial swirl three-dimensional combustor is studied and compared with the experimental values.The soot particles in the swirl combustor are controlled and reduced by changing the proportion of internal and external swirl and secondary flow.The results show that the decreasing of the proportion of Central swirl or the increasing of secondary flow will lead to the decreasing of soot concentration and distribution area.