The Research On Premixed Flame's Quenching Of Inert Gas In Duct

The research on premixed flame suppression in tubes with muti-wire meshes and inert gases are rarely reported.The research on hight speed flame's quenching in suppresing structure with inert gases is not only important to academia but also to the society.To investigate the rule of the flame's quenching in narrow channels with inert gases,the, quenching condition of premixed flames in muti-wire meshes with inert gases are researched experimentally and then simulated numerically in this paper.The main work and conclusions in this paper are as follows:(1) The experiment structure is improved to let the inert gases fill in the tube of various concentration,relalize the research on the quenching speed of C₂H₂/O₂/Inert Gas premixed flame.Acquire the relationship between the quenching speed and pressure and the the inert gases concentration and the wire mesh parameters.A concept,suppression parameter,was introduced to indicate the effects of suppressing explosion pressure and flame speed for a multilayer mesh.The experiment results reveal that the wire mesh can quenching the flame which has the larger speed and pressure with the higher inert gas concentration.It is that the mesh has better ability in quenching flame with higher inert gases concentration.(2) The geometrical model of wire mesh has been formed,simulate the process of the flame quenching in the wire mesh.Stimulate the premixed flame C₂H₂/O₂/Inert Gas quenched in wire mesh to make out the infulence of the inert gases to the flame quenching.Compare the result of the experiment and the simulation to assure the model is accurate.The simulation of C₂H₂/O₂/Inert Gas premixed flame quenching in wire mesh with different inert gases concentration are studied.It is found that there is more quenching layers as the concentration of inert gases increasing,it reveals the inet gases accelerate the flame quenching.Once the concentrations increase to some extent,the quenching lengths of flame in wire mesh will not change.Define the minimum concentration when quenching lengths change less than 1mm as the critical concentrantion.The critical concentration to different activity flames are separately:acetylene,4:1;propane,3:1;methane,4:1.(3) Analysis the mechanism of the flame quenching with inert gases.The comparation of the combustion in Oxygen and the inert gases reveals that the reason for flame extinguishing easier in inert gases can be explained that premixed mixtures are diluted with the complement of inert gases,which eventually leads to the reduction of reaction rate. (4) Compare the simulation results of the flame quenching in the wire mesh,duct,and the paralell paltes,helium is best to the flame quenching effect,and argon takes the second place, nitrogen is the worst.