This study quantitatively examines the impact of magnetic fields on methane flame characteristics,specifically analyzing changes in flame height,width,and velocity.Using flame photography and Particle Image Velocimetr...This study quantitatively examines the impact of magnetic fields on methane flame characteristics,specifically analyzing changes in flame height,width,and velocity.Using flame photography and Particle Image Velocimetry(PIV),the effects of varying magnetic field strengths(ranging from 25 to 45 mT)on flame behavior were measured across equivalence ratios(φ)from 0.8 to 2.0.The results reveal that applying a magnetic field increases flame height by up to 6.75%while reducing flame width by approximately 6%under a field strength of 45 mT atφ=2.0.Additionally,PIV data demonstrate a significant increase in upward flame velocity,with an observed enhancement of 20%at higher magnetic field intensities.The gradient magnetic field was found to reduce flame distortion,leading to a smoother flame profile.Compared to the control group(M0,with no magnetic field),these findings confirm that magnetic fields can effectively adjust flame properties.This study underscores the potential of magnetic fields in optimizing combustion processes.展开更多
Soot nanoparticles produced during combustion exhibit diverse nanostructures,which are affected by different combustion parameters such as flame stoichiometry and temperature.This work focuses on characterizing RP-3 j...Soot nanoparticles produced during combustion exhibit diverse nanostructures,which are affected by different combustion parameters such as flame stoichiometry and temperature.This work focuses on characterizing RP-3 jet flame properties and exploring the intricate relationship between the effect of temperature and carbon formation.The observed flame length displayed a notable increase in proportion to the equivalence ratio's growth.The flame color underwent a great transformation,evolving from pale blue in fuel-lean conditions to bright green at stoichiometric levels,and to brilliant yellow under fuel-rich conditions.Through systematic sampling and thorough observation of soot morphology at different flame heights,there is a clear correlation between the height of the flame and the acceleration of carbon agglomerate growth.Furthermore,an insightful observation is presented wherein the rise in flame height leads to a gradual reduction in the contribution of surface growth to the overall soot particle size.These findings contribute significantly to the understanding of the complex interplay between combustion conditions and soot nanostructures.The trends in flame characteristics,coupled with insights into soot morphology,provide a foundation for comprehending the underlying mechanisms governing soot formation in RP-3 flames.These results contribute to the understanding of combustion dynamics,offering valuable perspectives for optimizing combustion processes and elucidating the environmental implications of flame-formed soot.展开更多
基金financial support from the National Natural Science Foundation of China(No.52325604)National NSFC Ordered Synthesis and Low-Carbon Clean Combustion of Sustainable Aviation Fuels(SAF)(No.W2412101)+2 种基金MOST(2022YFB4003900/2021YFA0716200)National Science and Technology Major Project(J2019-Ⅲ-0005-0048)the Space Application System of China Manned Space Program。
文摘This study quantitatively examines the impact of magnetic fields on methane flame characteristics,specifically analyzing changes in flame height,width,and velocity.Using flame photography and Particle Image Velocimetry(PIV),the effects of varying magnetic field strengths(ranging from 25 to 45 mT)on flame behavior were measured across equivalence ratios(φ)from 0.8 to 2.0.The results reveal that applying a magnetic field increases flame height by up to 6.75%while reducing flame width by approximately 6%under a field strength of 45 mT atφ=2.0.Additionally,PIV data demonstrate a significant increase in upward flame velocity,with an observed enhancement of 20%at higher magnetic field intensities.The gradient magnetic field was found to reduce flame distortion,leading to a smoother flame profile.Compared to the control group(M0,with no magnetic field),these findings confirm that magnetic fields can effectively adjust flame properties.This study underscores the potential of magnetic fields in optimizing combustion processes.
基金financially supported by the National Key R&D Program (2021YFA0716200/ 2022YFB4003900)National Natural Science Foundation of China (No.52325604)the financial support from the ANSO scholarship。
文摘Soot nanoparticles produced during combustion exhibit diverse nanostructures,which are affected by different combustion parameters such as flame stoichiometry and temperature.This work focuses on characterizing RP-3 jet flame properties and exploring the intricate relationship between the effect of temperature and carbon formation.The observed flame length displayed a notable increase in proportion to the equivalence ratio's growth.The flame color underwent a great transformation,evolving from pale blue in fuel-lean conditions to bright green at stoichiometric levels,and to brilliant yellow under fuel-rich conditions.Through systematic sampling and thorough observation of soot morphology at different flame heights,there is a clear correlation between the height of the flame and the acceleration of carbon agglomerate growth.Furthermore,an insightful observation is presented wherein the rise in flame height leads to a gradual reduction in the contribution of surface growth to the overall soot particle size.These findings contribute significantly to the understanding of the complex interplay between combustion conditions and soot nanostructures.The trends in flame characteristics,coupled with insights into soot morphology,provide a foundation for comprehending the underlying mechanisms governing soot formation in RP-3 flames.These results contribute to the understanding of combustion dynamics,offering valuable perspectives for optimizing combustion processes and elucidating the environmental implications of flame-formed soot.
