Numerical And Experimental Study On Premixed Combustion Of Multi-Component Gaseous Fuel In Porous Media

Porous medium combustion technology is an advanced gas fuel combustion technology.Compared to general burners,porous medium combustion has significant advantages in improving combustion efficiency,reducing pollutant emissions,expanding flammability limits,and enhancing heat exchange efficiency.However,in practical applications,there are still many unstable factors in the actual operating conditions of porous medium burners,and existing research on the radiation performance analysis of porous medium burners is not comprehensive enough.Based on existing research on porous media,this article conducts an in-depth analysis of the effects of adding CO₂ to fuel on the operational stability,pollutant emission characteristics,and burner radiation performance of honeycomb ceramic porous media burners.At the same time,discuss the current research hotspots on how to use porous media to achieve efficient combustion of ammonia.First of all,this paper designed a multi-layer medium structure burner experimental system.Through the thermocouple array,the temperature distribution of each layer of medium during propane combustion in the honeycomb ceramic porous medium burner under various working conditions was measured.Through the temperature distribution of different layers,combined with the running time,the flame propagation speed was obtained,and the effects of adding CO₂ were compared and analyzed.The results indicate that at a lower heat load of 200 k W/m²,the excess air coefficient is between 1.0 and 1.7（Φ）Stable stationary combustion on the surface of the burner within the range.When the flame moves,excess air has a more significant impact on flame propagation in honeycomb ceramics compared to thermal load.In addition,CO₂ has a significant slowing effect on the propagation of propane premixed flames in honeycomb ceramics.This slowing effect is more pronounced when the excess air coefficient is 1.2,and the slowing effect increases with the increase of CO₂ content.Secondly,this article also designed another double-layer medium structure burner experimental system.This experiment used a flue gas analyzer and a radiation meter to explore the effect of CO₂ addition on the performance of the burner.In terms of pollutant emissions,CO₂ caused an increase in CO emissions to varying degrees,while the effect of adding CO₂ on the NOx emissions of the burner was not significant.In addition,the addition of CO₂ showed different effects on the radiation performance of different excess air coefficients under three heat loads of 200 k W/m²,400 k W/m²,and 600 k W/m².When the excess air coefficient is 1.2,the addition of CO₂ has little effect on the radiation performance of the burner under three heat loads.Finally,this article compared the combustion performance of ammonia in different porous media burners and found that the results in pollutant emissions were not ideal,and the NOx emissions from combustion in both burners were relatively high.In terms of radiation performance,compared with honeycomb ceramic burner,foam ceramic burner has more stable radiation output capacity.In general,in terms of pollutant emission and output power,the operating results of both burners cannot meet the standards of practical application,but the performance results of foam ceramic burners are more advantageous.