Study On The Influence Of Pulse-jet Airflow Deflection On The Performance Of Filter Cartridge And Its Optimization

In the process of filter cartridge pulse jet cleaning,there is a phenomenon of air flow deflection,which will not only cause uneven cleaning of the filter cartridge,but also shorten it’s service life.In this experiment,numerical simulation,experimental test and industrial test will be used to carry out research on the influence parameters of airflow deflection,revealing the influence of jet airflow deflection on the cleaning performance of the filter cartridge.(1)The results of schlieren method and numerical simulation show that the diameter of the jet hole has the greatest influence on the deflection angle of the airflow,followed by the distribution of the jet hole,and finally the injection pressure.The deflection angle is positively correlated with the diameter of the nozzle,and the relation between them can be expressed θ=0.04452*d^2+0.05714*d+1,the degree of deflection of the jet-hole decreases gradually along the axial direction of the pulse-jet pipe,and the maximum angle of deflection decreases by 50 percent.(2)For different jet pressure,different jet-hole diameter,different jet distance,The influence of airflow deflection on the pressure of filter cartridge was investigated by atmospheric pressure pulse jet experiment.As a result,the airflow deflection mainly acts on the upper part of the filter cartridge(the maximum difference of the wall is up to 796.2 Pa),have little effect on the lower part of the filter cartridge(the minimum difference can be 2.8Pa).Among them,When the injection pressure increases from 0.4 MPa to 0.5 MPa,The peak pressure increases,However,the pressure difference on the side wall of the filter cartridge does not change much.When the injection distance increases from 60 mm to 270 mm,The pressure difference of the upper part of the filter cartridge is reduced and then increased under the deflection of each hole area,The optimum working conditions are: nozzle diameter14 mm,injection distance 240 mm,injection pressure 0.4 MPa.The effect of deflection between the holes on the same pulse-jet pipe is filter cartridge1>2>3.(3)The results show that the use of right angle diversion nozzle can greatly improve the phenomenon of airflow deflection and its adverse effects.The percentage of pressure difference between the surface of face-flow and back-flow of filter cartridge decreased from27.2～47.62% to 10～20%.The maximum difference percentage is reduced to 2.53%,but the airflow pressure loss is increased.Compared with the jet flow,the side wall pressure loss is about 30%.(4)Experimental results of industry verify that there is a significant gap of residual amount of dust on the upper surface of the filter cartridge before correction,with a maximum of 88 g,the residual amount of dust of the filter cartridge away from the pulse valve is less than that near the pulse valve.