Experimental Study On Temperature Distribution Of Methane Premixed Combustion In The Free Stacking Small Sphere Porous Medium

Compared with the traditional free flame combustion,the premixed combustion of porous media has the advantages of high heat transfer efficiency,low pollutant emissions and a wide range of combustion limits and so on.Therefore,it has important application prospects in civilian infrared burners,industrial exhaust gas combustion purification and new super adiabatic combustion technologies.The combustion temperature characteristics of porous media are important technical indicators,which affects the combustion efficiency and the generation of pollutants.Because of the porous structure of the porous media,the internal heat transfer involves the coupled heat transfer process of various heat transfer modes,such as forced convection heat transfer between solid skeleton and air flow,solid skeleton heat transfer,radiation heat transfer of solid skeleton,and heat release from fuel combustion.Generally speaking,experimental measurements are a reliable technique for obtaining burner temperature distribution.In this thesis,the premixed combustion experimental system for free stacking sphere porous medium is set up.The temperature measurement method includes thermocouple arrays,monochromatic thermometers,and infrared thermal imaging cameras,aiming at measuring the temperature distribution of the free stacking sphere porous medium.On the one hand,using thermocouple array experiments to measure the effect of equivalence ratio and the test parameters are stacking ball diameter and combustion intensity on the dynamic changes.On the other hand,the temperature variation characteristics of the axial side surface of the combustion chamber have been measured with a monochromatic thermometer and an infrared camera,and the temperature distribution of the accumulated ball surface at the combustion chamber's outlet has been measured by using an infrared camera.The influencing factors and changing rules of temperature distribution are analyzed.The approximate three-dimensional temperature distribution information of the free stacking sphere burner is obtained,which provides technical support for analyzing pollutant emission characteristics and regulating methods.Using flue gas analyzer measuring the concentration of pollutants in flue gas combustion porous medium.The effects of pollutant concentration are studied,which the test parameters include equivalence ratio,stacking ball diameter and combustion intensity.According to the experimental research,we deeply acquaint the application characteristics of thermocouple temperature measurement in the premixed combustion of free stacking sphere porous medium.The combustion temperature distribution of free stacking sphere porous medium was obtained by three kinds of temperature measurement methods.The influence of the equivalence ratio,tstacking sphere diameter,the combustion intensity and other factors on the temperature distribution and pollutant emission of the free stacking sphere porous medium burner are mastered.Obtained the best value range of combustion equivalence ratio.It provides a reference for the development of combustion technology for free stacking sphere porous medium.