Near-Nozzle Atomization Characteristics in Air-Assisted Spraying: Integrated VOF-DPM Modeling and Experimental Validation
Source abstract
Abstract
Near-nozzle atomization characteristics in air-assisted spraying were investigated through a novel 3D transient model integrating Volume-of-Fluid and Large Eddy Simulation (VOF-DPM) methods, with experimental validation of droplet distributions (Malvern analyzer) and coating thickness profiles. Key findings reveal that (1) the spray field stabilizes within 30 mm downstream, achieving 80% atomization efficiency (droplets ≤ 100 μm) at 27.5 mm axial distance; (2) radial momentum originates dually from fan-shaped airflow (max 595 m/s) and transverse motion induced by central atomizing air entrainment—a previously unreported mechanism; (3) paint loading delays flow stabilization to 2.5 ms (vs. 0.7 ms for gas-only flow) while reducing peak axial velocity by 18%–22% due to gas–liquid momentum exchange; (4) auxiliary and fan airflows synergistically constrain dispersion, forming elliptical sprays with characteristic cone angles of 61.7° (short axis) and 99.1° (long axis). Significantly, surface tension plays a dual role in inhibiting droplet atomization while promoting ligament pinch-off at 8.1 mm breakup length. These results provide the first quantitative characterization of gas–liquid interactions in near-nozzle regions, enabling precise parameter control for enhanced coating uniformity on complex surfaces.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Fluid Dynamics and Heat Transfer · Aerosol Filtration and Electrostatic Precipitation · Plant Surface Properties and Treatments
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Petroleum, Engineering University of the Joint Logistic Support Force, Chongqing 401331, China
National Engineering Research Center for Disaster and Emergency Rescue Equipment, Engineering University of the Joint Logistic Support Force, Chongqing 401331, China
Funding
Natural Science Foundation of China · Natural Science Foundation of Chongqing, China · Science and Technology Research Program of Chongqing Municipal Education Commission
References (23)
Show source-provided references
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