Study On The Laminar Combustion Characteristics Of Blast Furnace Gas And Natural Gas Mixed Fuel

Blast furnace gas has extremely high application value in power machinery such as engines and gas turbines.However,the extremely low calorific value causes difficulties for stable combustion.In order to use blast furnace gas more fully and reasonably,it is necessary to know its combustion characteristics while the basic research on blast furnace gas is not yet complete.For this purpose,this article conducted experimental measurements and simulation calculations for blast furnace gas and mixture of blast furnace gas and natural gas,in order to analyze the laminar combustion characteristics of the fuels,so as to establish and improve the basic combustion database of blast furnace gas,and finally provide theoretical and technical support to performance optimization and structural improvement of the combustion chamber.Through the constant volume combustion reaction experiment,test the laminar burning characteristics of blast furnace gas,the lowest heat value is 4.03MJ/Nm3,when the initial temperature is 303K,353K,403K,453K,and the initial pressure is 0.1MPa,0.15MPa,0.2MPa,and the equivalent ratio is from 0.8 to 1.6.Use CHEMKIN software to simulate and calculate the laminar burning process of blast furnace gas with different low heat value and different composition ratio under the above working conditions.The research results show that the laminar burning speed of blast furnace gas increases with the increase of the initial temperature or the decrease of the initial pressure.At low equivalence ratio,the increase in temperature is conducive to the stable combustion of blast furnace gas.At high equivalence ratio,when the temperature increases,the combustion stability will be deteriorated.It can be found from the analysis that the chemical reaction kinetics effect is the main factor affecting the laminar burning speed of blast furnace gas.During the combustion process,the increase in the concentration of highly reactive free radicals can effectively increase the laminar burning speed of blast furnace gas.Mix natural gas and blast furnace gas which has different calorific value and composition ratio in different methane mixing ratio.Through the constant volume combustion reaction experiment,test the laminar combustion characteristics of the mixture at 453K and 0.2MPa with the equivalent ratio from 0.8 to 1.4.Use CHEMKIN software to simulate and analyze the laminar combustion process of the mixture under the above conditions.The research results show that at low equivalence ratio,as the mixing ratio of methane in natural gas increases,the laminar burning speed of the mixture increases,and the thermal effect mainly affects the laminar burning speed.At high equivalence ratios,the laminar burning speed of the mixture decreases with the increase of methane content,and the kinetic effect of chemical reaction mainly affects the laminar burning speed of the fuel.