Abstract
In order to understand the characteristics of the spray field of a dust suppression nozzle and provide a reference for dust nozzle selection according to dust characteristics, a three-dimensional phase Doppler particle analyzer (PDPA) spray measurement system is used to analyze the droplet size and velocity characteristics in a spray field, particularly the joint particle size–velocity distribution. According to the results, after the ejection of the jet from the nozzle, the droplets initially maintained some velocity; however, the distribution of particles with different sizes was not uniform. As the spray distance increased, the droplet velocity decreased significantly, and the particle size distribution changed very little. As the distance increased further, the large droplets separated into smaller droplets, and their velocity decreased rapidly. The distributions of the particle size and velocity of the droplets then became stable. Based on the particle size-velocity distribution characteristics, the spray structure of pressure-swirl nozzles can be divided into five regions, i.e., the mixing, expansion, stabilization, decay, and rarefied regions. The expansion, stabilization, and decay regions are the effective dust fall areas. In addition, the droplet size in the stabilization region is the most uniform, indicating that this region is the best dust fall region. The conclusions can provide abundant calibration data for spray dust fall nozzles.
Highlights
With the development of efficient mechanization, the amount of coal mine dust is increasing.The high concentration of dust on the production site is very harmful, as it brings harm to the physical and mental health of underground workers, and threatens the production safety of coal mines
Zhou et al [19] used the Malvern laser particle size analyzer to conduct tests involving the atomization particle size under various pressures. They found that the droplet size is the smallest at the center of the spray field and gradually increases towards the edge
We used a three-dimensional (3-D) phase Doppler particle analyzer (PDPA) spray measurement system to analyze the distributions of different droplet sizes and velocities in the spray field, the joint particle size–velocity distribution, to fully understand the spatial movements of droplets as the spray distance increases and provide a large amount of calibration data for spray structure
Summary
With the development of efficient mechanization, the amount of coal mine dust is increasing. Zhou et al [19] used the Malvern laser particle size analyzer to conduct tests involving the atomization particle size under various pressures They found that the droplet size is the smallest at the center of the spray field and gradually increases towards the edge. Pollock et al [22] used a phase Doppler particle analyzer (PDPA) to investigate water droplet size and velocity characteristics for hollow-cone, full-cone, flat-fan, and air-atomizing spray nozzles at similar operating parameters. We used a three-dimensional (3-D) PDPA spray measurement system to analyze the distributions of different droplet sizes and velocities in the spray field, the joint particle size–velocity distribution, to fully understand the spatial movements of droplets as the spray distance increases and provide a large amount of calibration data for spray structure. We can further understand the characteristics of the droplets in the spray field of the dust nozzle and provide a reference for dust nozzle selection according to dust characteristics
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
