Effect Of Magnetic Field On Premixed Laminar Flame And Generation Characteristics Of Nitrogen Oxide

With the sustained and stable development of the economy, pollutant emissions inrapidly increasing harm to human beings is also enhanced. The control and emissions ofnitrogen oxide is an important evaluation of clean combustion, and the affection of manyother factors on nitrogen oxide emissions also become scholars investigate the difficulties athomeandabroad inrecentyears.In this paper, take the laminar premixed flame for study, which get the experimentalmeasurements that the influence of magnetic on flame and nitrogen oxides’ generatedcharacteristics. It provides the basis research data to control the production of nitrogen oxidesinthecombustionprocess.Take a combustion test rig built， use electromagnets to achieve magnetic fieldadjustment; use the platinum-rhodium thermocouple and digital thermometer to monitor thetemperature of the flame; utilize flue gas analyzer to monitor the concentration of nitrogenoxides; use HD camera monitoring the flame shape. It completed a laminar premixedcombustion experiment under the different flows and magnetic fields. measured the flamelength，flame diameter, while measuring the magnetic field strength, the flame temperatureand theNOxconcentration onthe differentlengthoftheflame.Analysis the premixed flame combustion characteristics and NOxformationcharacteristics at different magnetic field strength. The results showed that under the actionof electromagnetic field, as compared with non-magnetic, laminar flame in theelectromagnetic field is more intense, the premixed flame length becomes shorter, thicker indiameter. In a gradient magnetic field, the lager of the magnetic field strength, the higher ofthe temperature of flame surface, and with the increase of the field strength increases. Instrength magnetic area, containing N ions or ionic groups subjected to the role of the Lorentzforce, so that take the original movement from disorder with the flow upward into a regular direction of the force. When the liquefied gas flow is4.5,3,2L/h, NOxconcentrations get thelargestdeclineof23.9%,21.9%and23.5%.At the flame combustion process, the fuel pyrolysis must be become some charged orionic groups within the flame, and these ions and the ionic groups do not immediatelycombined with oxygen formed molecules, while there will be some time in the form of ions.Distribution and movement form of ions and ion groups have a greater impact to generationof nitrogen oxides. When the flame in a magnetic field, the Lorentz force will changes thetrajectory of ions and the ionic groups generated in the combustion process, buy thedisordered motion into regular exercise under certain trajectory, and thus the speed ofchemical reactions during combustion of various reactants have changed, last affecting thegenerationcharacteristics ofNOx.