Abstract
A mathematical model of the cavity flow of the fan nozzle, a mathematical model of jet atomisation, and a simplified physical model of the equivalent entity are established. A simulation of the spraying flow at different spraying pressures is carried out using a 0.48 calibre nozzle as a case study, and compared with experimental data; error results between 4.3% and 7.5% indicate the simulation means used are reliable and the simulation model is valid. The simulation means include using the effective simulation model to further explore the evaluation index of atomisation characteristics; in the critical Weber number on the impact of atomised particles, analysis of the impact of the critical Weber number on the diameter of atomised particles and the speed of movement, and determining the critical Weber number; atomisation spraying effect, for atomisation pressure on atomised particle diameter, speed of movement, impact kinetic energy, deposition rate, and liquid film growth, etc. The results show that, in the existing high-pressure airless spraying equipment within the range of permissible pressure 6~16 MPa, with the increase in atomisation pressure, the better the atomisation effect of the paint, the better the atomised particle spraying adhesion deposition rate of the paint, and the better the overall spraying effect.
Highlights
Due to the high corrosiveness and wave impact of the deep sea operation area, the coating and anti-corrosion of large-scale offshore engineering equipment is very important
The Computational fluid dynamics (CFD) software combines theoretical derivation and experiment to propose a mathematical model of fan spraying Flat-Fan-Atomizer atomization model that is more compatible with high-pressure airless spraying, which considers that the jet is ejected from a slender nozzle to form a flat liquid film, and broken under the action of air to form droplets
Atomisation pressure will have a direct impact on the atomisation effect of the paint, in4.c3l.uDdirnogpledtrIompplaecttdKiianmeteicteErnaenrgdy sApneaeldys,iswhich in turn leads to a change in the impact kinetiAc etonmerigsaytEionwphreenssthueredwroiplllhetavtoeuachdeirsetchteimwpaallc.tTohnetihmepaatoctmkiisnaettioicneenfefergctyooffthaesipnagilnet, dirnocpluledtindgurdirnogptlhetedsiparmayeitnergapnrdocsepseseids,mwohriechobinvitouurns cleoamdpsatoreadcwhaitnhgtehiencthhaenigmepinacdt rkoinpeletitc deinaemrgetyerEawnhdesnpteheedd. rDorpolpetlettoukcinhetsictheenweraglyl. aTnhde ismprpaaycitnkgindeitsitcanenceragnydofthaesirneglalteiodnrsohpilpet bdeutwrienegnththeespspraryaiynigngprporceessssuirsemisosrheoowbvnioinusTcaobmlep7a.red with the change in droplet diameter and speed
Summary
Due to the high corrosiveness and wave impact of the deep sea operation area, the coating and anti-corrosion of large-scale offshore engineering equipment is very important. In 2013, Qiaoyan Ye et al conducted an experimental study of the droplet size distribution and droplet velocity required for the simulation by applying a computational fluid dynamics program to the flow field and droplet trajectory, using a Spraytec-Fraunhofer type particle size meter and a laser Doppler anemometer, pointing out the effects of wind speed and spray distance on the target surface transfer efficiency and paint film thickness distribution [9]. In 2018, Qiaoyan Ye et al conducted a numerical study of the spraying process using three atomisers: a high-speed rotary nozzle, an airless gun, and a pneumatic air gun, and the simulation results showed that the impact droplet characteristics of the three atomisers differed significantly and had a large impact on the performance of the paint film.
Sign-in/Register to view highlights & summary 
Published Version (
Free)
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 call