| As a new t angential firing technology , the wall tangential firing technology hasa good prospect of engineering application in Supercritical and Ultra Supercriticaltechnologies . It has good jet r igidity , s mall deflection of jets, uniform heat loaddistribution on wall and good c ombustion stability . To research the gas/particle towphase flow characteristics in the wall tangential firing technology, Tracer test s andcold experiment s are conducted on the modeling test-bed of an supercritical boileradopting h orizontal bias combustion technology and PM v ertical bias combustiontechnology r espectively .With Particle dynamics analyzer(PDA) measurement system, the experimentshave benn conducted to investigate the effect of the bias of primary air nozzles andp rimary air ratio on the characteristics of aerodynamics fields in the burner zone, thedistribution of the gas/particle velocity and particle concentration of the primary air,as well as the velocity attenuation characteristics are obtained.The experimental results indicate that: For the horizontal burner, with thechange of the primary air nozzles bias form 0°to 8°, the tangential circle becomesmaller and the primary air jets proliferation reduce; Also improve the flowcontaining particles flush to the water wall and prevent slagging; The a ttenuation ofthe primary air jets is slowest when the primary iar nozzles bias is 5°; With theincrease of the primary air ratio, the rigidity and penetrating of the primary air jets isstrong apparently, the primary air jets are difficult to deflect and the jets p roliferationis weaken and the a ttenuation of the primary air jets become rapid obviously. For thePM v ertical b urner , because the a spect ratio of the burner(h/b) is large and exceed theu pper limit with the good rigidity of jets, the high of flow is large and the a djacentjets c ollide strongly, the rigidity of the primary air jets is bad, the deflection ofprimary air jets is s erious and the tangential circle become bigger. With the increaseof the primary air ratio, the deflection of the primary air jets is improved. T hea ttenuation of fuel-poor jet is slow with the increase of the primary air ratio and theattenuation of fuel-rich jet is rapid with the increase of the primary air ratio.T he distribution of particle concentration of the primary air is similar to thevelocity distribution. Uniform distribution of particle concentration can be obtainedwhen the penetrating of the primary air jets is strong, otherwise, the slagging maybecome worse. B ase on the comparison the horizontal burner with the PM vertical burner, thejet r igidity of the horizontal burner is better than the PM vertical burner. T he resultsof the cold experiments for the wall tangential firing technology can provide somesuggestions and guides on further explore of the wall tangential firing technology. |
