Drop-on-demand painting of highly viscous liquids
An on-demand painting system with a simple structure device that ejects highly viscous liquids as microjets is introduced. An impulsive motion of the container results in the ejection of a viscous liquid jet from the nozzle. This system enabled us to paint letters on a section of a car body using co...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Cambridge University Press
2021-01-01
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| Series: | Flow |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S2633425921000076/type/journal_article |
| _version_ | 1811156282551304192 |
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| author | Kyota Kamamoto Hajime Onuki Yoshiyuki Tagawa |
| author_facet | Kyota Kamamoto Hajime Onuki Yoshiyuki Tagawa |
| author_sort | Kyota Kamamoto |
| collection | DOAJ |
| description | An on-demand painting system with a simple structure device that ejects highly viscous liquids as microjets is introduced. An impulsive motion of the container results in the ejection of a viscous liquid jet from the nozzle. This system enabled us to paint letters on a section of a car body using commercial car paint with a zero-shear viscosity of 100 $\textrm {Pa} \cdot \textrm {s}$. To understand the jet velocity, we conducted systematic experiments. Experimental results showed that the jet velocity increases with the ratio between the liquid depths in the container and the nozzle, up to approximately 30 times faster than the initial velocity. However, a linear relation between the jet velocity and the ratio predicted by the previous model, which considers only the pressure impulse, does not hold for the high length ratios since the actual position of the stagnation point is different from the position predicted by the previous model. By solving the Laplace equation and using the model proposed by Gordillo et al. (J. Fluid Mech., vol. 894, 2020, pp. A3–11), we reproduce the non-monotonic behaviour of the jet velocity as a function of the length ratio. For practical use, we improve the jet-velocity model by considering mass conservation as well as the pressure impulse. |
| first_indexed | 2024-04-10T04:48:59Z |
| format | Article |
| id | doaj.art-131b2988ac4f400d99d73fe5aaf26f2f |
| institution | Directory Open Access Journal |
| issn | 2633-4259 |
| language | English |
| last_indexed | 2024-04-10T04:48:59Z |
| publishDate | 2021-01-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Flow |
| spelling | doaj.art-131b2988ac4f400d99d73fe5aaf26f2f2023-03-09T12:34:16ZengCambridge University PressFlow2633-42592021-01-01110.1017/flo.2021.7Drop-on-demand painting of highly viscous liquidsKyota Kamamoto0Hajime Onuki1Yoshiyuki Tagawa2https://orcid.org/0000-0002-0049-1984Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, JapanDepartment of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, JapanDepartment of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, JapanAn on-demand painting system with a simple structure device that ejects highly viscous liquids as microjets is introduced. An impulsive motion of the container results in the ejection of a viscous liquid jet from the nozzle. This system enabled us to paint letters on a section of a car body using commercial car paint with a zero-shear viscosity of 100 $\textrm {Pa} \cdot \textrm {s}$. To understand the jet velocity, we conducted systematic experiments. Experimental results showed that the jet velocity increases with the ratio between the liquid depths in the container and the nozzle, up to approximately 30 times faster than the initial velocity. However, a linear relation between the jet velocity and the ratio predicted by the previous model, which considers only the pressure impulse, does not hold for the high length ratios since the actual position of the stagnation point is different from the position predicted by the previous model. By solving the Laplace equation and using the model proposed by Gordillo et al. (J. Fluid Mech., vol. 894, 2020, pp. A3–11), we reproduce the non-monotonic behaviour of the jet velocity as a function of the length ratio. For practical use, we improve the jet-velocity model by considering mass conservation as well as the pressure impulse.https://www.cambridge.org/core/product/identifier/S2633425921000076/type/journal_articleBreakup/CoalescenceDropsJetsInk jets |
| spellingShingle | Kyota Kamamoto Hajime Onuki Yoshiyuki Tagawa Drop-on-demand painting of highly viscous liquids Flow Breakup/Coalescence Drops Jets Ink jets |
| title | Drop-on-demand painting of highly viscous liquids |
| title_full | Drop-on-demand painting of highly viscous liquids |
| title_fullStr | Drop-on-demand painting of highly viscous liquids |
| title_full_unstemmed | Drop-on-demand painting of highly viscous liquids |
| title_short | Drop-on-demand painting of highly viscous liquids |
| title_sort | drop on demand painting of highly viscous liquids |
| topic | Breakup/Coalescence Drops Jets Ink jets |
| url | https://www.cambridge.org/core/product/identifier/S2633425921000076/type/journal_article |
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