Study On Atomization Performance And Optimization Of Air-assisted Spray Dust Suppression Device

The air-driven spray dust suppression device is a new type of spray dust removal equipment.It uses high-speed airflow as a carrier.When the airflow reaches the spray port through the nozzle,the spray from the pressure nozzle is further broken,and the interference between multiple nozzles is used to increase the concentration of droplets,and then transport the droplets to the prevention and control target.The air-driven spray dust suppression device has the advantages of long range,strong fog flow penetration,slow fog drop settling and good adhesion,so it can be used in a variety of workplaces.At now,researchers have focused more on the improvement of the internal structure of the air-driven spray dust suppression device,but the selection of the nozzle of the air-driven spray dust suppression device and the atomization effect of the droplets under the interference of multiple nozzles are not in-depth study.Therefore,I choose the JJPW-G100 air-driven spray dust suppression device produced by Hunan Jiujiu Intelligent Environmental Protection Co.,Ltd.,and use a combination of numerical simulation and experiment to optimize the common nozzles of the air-driven spray dust suppression device at this stage.Analyzed the atomization characteristics under the interference of multiple nozzles and the atomization performance parameters of the spray field of the air blown spray dust suppression device,so as to explore the distribution law of the atomization parameters of the spray field of the air blow spray dust suppression device.The main working condition parameters of the device were optimized,and the best nozzle installation angle and air cylinder injection angle were determined,and finally applied to the actual project site to measure its dust reduction efficiency.The main conclusions of the study are as follows:（1）Under the effect of multi-nozzle interference,the overall droplet size and droplet concentration are larger than that of a single-nozzle atomization performance,but the minimum droplet size is close to the single-nozzle minimum droplet size.（2）The droplet particle size distribution of the air-driven spray dust suppression device is basically in line with the small particle size droplet distribution in the upper part of the spray field,and the lower part of the spray field is the larger droplet.The minimum particle size of the droplets in the spray field remains basically unchanged,while the average particle size and the maximum particle size show a trend of first increasing and then decreasing with the increase of the spray distance.As the distance increases,the average droplet size gradually stabilizes.The wind velocity field in the spray field weakens rapidly with the increase of the spray range,and the wind flow mainly affects the upper half of the spray field.（3）As the nozzle installation angle increases,the overall droplet size increases,but the minimum droplet size remains the same.The falling range of the spray field gradually increases with the increase of the nozzle installation angle.Because the droplet size in the effective dust reduction range is not greatly affected by the nozzle installation angle,the droplet concentration in the spray field increases with the nozzle installation angle,and the falling range increases with the nozzle installation angle.And when the nozzle installation angle is less than 45°,the droplet phenomenon occurs at the spray outlet,so the nozzle installation angle of 45° is the best.（4）With the increase of the angle of the air duct,the spray range first increases and then decreases.When the angle of the air duct increases to 30°,the spray field appears to rotate significantly.When the spray range is small,the average particle size and maximum particle size of the droplets increase with the increase of the angle of the air cylinder,while the minimum particle size of the droplets remains basically unchanged.With the increase of the range,the minimum particle size,average particle size,and maximum particle size of the droplets at all air cylinder angles gradually decrease.Therefore,in order to avoid the rotation of the spray field,the air duct angle of 20° can be effectively used for dust reduction in practical engineering applications.（5）After adjusting the working parameters of the air-driven spray dust suppression device to the selected optimized data,sampling the five measurement points selected on the project site to obtain the dust concentration,dust particle size distribution and total dust reduction efficiency and respirable dust reduction before and after dust fall.By comparing and analyzing the dust reduction efficiency,it is concluded that the main dust-producing area needs to be adjusted to the best dust reduction range of the air-driven spray dust suppression device in the field application to obtain a better dust reduction effect.