Please use this identifier to cite or link to this item:
http://hdl.handle.net/10397/2486
| Title: | Self-focused acoustic ejectors for viscous liquids | Authors: | Hon, SF Kwok, KW Li, HL Ng, HY |
Issue Date: | Jun-2010 | Source: | Review of scientific instruments, June 2010, v.81, no. 6, 065102, p. 1-6 | Abstract: | Self-focused acoustic ejectors using the Fresnel zone plate (FZP) have been developed for ejecting viscous liquids, without nozzle, in the drop-on-demand mode. The FZP is composed of a lead zirconate titanate piezoelectric plate patterned with a series of annular electrodes, with the unelectroded region of the plate removed. Our results show that the acoustic waves are effectively self-focused by constructive interference in glycerin (with a viscosity of 1400 mPa s), giving small focal points with a high pressure. Due to the high attenuation, the wave pressure decreases significantly with the distance from the FZP. Nevertheless, the pressure at the focal points 2.5 and 6.5 mm from the FZP is high enough to eject glycerin droplets in the drop-on-demand mode. Driven by a simple wave train comprising a series of sinusoidal voltages with an amplitude of 35 V, a frequency of 4.28 MHz, and a duration of 2 ms, the ejector can eject fine glycerin droplets with a diameter of 0.4 mm at a repetition frequency of 120 Hz in a downward direction. Droplets of other viscous liquids, such as the prepolymer of an epoxy with a viscosity of 2000 mPa s, can also be ejected in the drop-on-demand mode under similar conditions. | Keywords: | Acoustic waves Drops Fresnel diffraction Nozzles Piezoelectric devices Plastic flow |
Publisher: | American Institute of Physics | Journal: | Review of scientific instruments | ISSN: | 0034-6748 | EISSN: | 1089-7623 | DOI: | 10.1063/1.3442526 | Rights: | © 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in S.F. Hon et al., Rev. Sci. Instrum. 81, 065102 (2010) and may be found at http://link.aip.org/link/?rsi/81/065102 |
| Appears in Collections: | Journal/Magazine Article |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| RevSciInstrum_81_065102.pdf | 415.12 kB | Adobe PDF | View/Open |
Access
View full-text via PolyU eLinks 
Page views
130
Last Week
1
1
Last month
Citations as of Oct 1, 2023
Downloads
198
Citations as of Oct 1, 2023
SCOPUSTM
Citations
10
Last Week
0
0
Last month
0
0
Citations as of Sep 28, 2023
WEB OF SCIENCETM
Citations
9
Last Week
2
2
Last month
1
1
Citations as of Sep 28, 2023
Google ScholarTM
Check
Altmetric
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.