Paint Film Formation Characteristics on Conical Surfaces for Electrostatic Air Spray Painting
Abstract
:1. Introduction
2. Paint Droplets Transport Model
2.1. Approach
2.2. Electrostatic Field
2.3. Motion Trajectory of the Charged Droplets
3. Numerical Simulation Setup
3.1. The Computational Domain
3.2. Continuous Phase
3.3. Discrete Phase
4. Results and Discussion
4.1. Continuous Phase
4.3. Paint Film Deposition Thickness Distribution and Transfer Efficiency
5. Experimental Investigation
6. Conclusions
- (1)
- Compared with the conical surface sprayed, the maximum film thickness on the planar target is the greatest. As the curvature of the conical target increases, the maximum film thickness decreases, and the paint film distribution range becomes narrow.
- (2)
- For a curved sprayed target, the airflow diffuses the fastest along the direction of maximum curvature on the target surface. With an increase in the curvature of the conical target, the flow field velocity near the wall region of the sprayed surface increases, and the number of small droplets carried by the airflow increases, while the number of droplets deposited on the target decreases, resulting in a lower paint transfer efficiency.
- (3)
- With an increase in the curvature, except for the spray center, the electric potential lines in the near-wall region are sparser, and the electric field force acting on the charged paint droplets is weakened. The paint transfer efficiency decreases with an increase in the curvature of convex conical surfaces.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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Paint Viscosity | Paint Density | Paint Surface Tension | Paint Electrical Conductivity | Air Density | Air Viscosity |
---|---|---|---|---|---|
1200 kg/m3 | 71.9 mN/m |
Curvature of Conical Targets | Maximum Thickness/μm | Maximum Thickness on X Section/μm | Maximum Thickness on Y Section/μm |
---|---|---|---|
0 | 39.588 | 39.2 | 35.2 |
2.28 × 10−3 | 38.223 | 38.4 | 33.7 |
3.29 × 10−3 | 36.285 | 35.5 | 31.8 |
4.78 × 10−3 | 34.215 | 31.9 | 30.3 |
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Zhang, S.; **, J.; Wu, S.; Jia, L.; Ma, X. Paint Film Formation Characteristics on Conical Surfaces for Electrostatic Air Spray Painting. Coatings 2023, 13, 1808. https://doi.org/10.3390/coatings13101808
Zhang S, ** J, Wu S, Jia L, Ma X. Paint Film Formation Characteristics on Conical Surfaces for Electrostatic Air Spray Painting. Coatings. 2023; 13(10):1808. https://doi.org/10.3390/coatings13101808
Chicago/Turabian StyleZhang, Shuzhen, Jiongde **, Shijie Wu, Lun Jia, and Xujie Ma. 2023. "Paint Film Formation Characteristics on Conical Surfaces for Electrostatic Air Spray Painting" Coatings 13, no. 10: 1808. https://doi.org/10.3390/coatings13101808