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Research Papers

Computational Fluid Dynamics Modeling and Online Monitoring of Aerosol Jet Printing Process

[+] Author and Article Information
Roozbeh (Ross) Salary, Jack P. Lombardi, M. Samie Tootooni, Ryan Donovan, Peter Borgesen, Mark D. Poliks

Department of System Science and
Industrial Engineering (SSIE),
Binghamton University,
State University of New York,
Binghamton, NY 13902

Prahalad K. Rao

Department of Mechanical and
Materials Engineering (MME),
University of Nebraska-Lincoln,
Lincoln, NE 68588-0526
e-mails: rao@unl.edu; prao@binghamton.edu

1Corresponding author.

Manuscript received April 21, 2016; final manuscript received August 10, 2016; published online October 3, 2016. Assoc. Editor: Donggang Yao.

J. Manuf. Sci. Eng 139(2), 021015 (Oct 03, 2016) (21 pages) Paper No: MANU-16-1239; doi: 10.1115/1.4034591 History: Received April 21, 2016; Revised August 10, 2016

The objectives of this paper in the context of aerosol jet printing (AJP)—an additive manufacturing (AM) process—are to: (1) realize in situ online monitoring of print quality in terms of line/electronic trace morphology; and (2) explain the causal aerodynamic interactions that govern line morphology based on a two-dimensional computational fluid dynamics (2D-CFD) model. To realize these objectives, an Optomec AJ-300 aerosol jet printer was instrumented with a charge coupled device (CCD) camera mounted coaxial to the nozzle (perpendicular to the platen). Experiments were conducted by varying two process parameters, namely, sheath gas flow rate (ShGFR) and carrier gas flow rate (CGFR). The morphology of the deposited lines was captured from the online CCD images. Subsequently, using a novel digital image processing method proposed in this study, six line morphology attributes were quantified. The quantified line morphology attributes are: (1) line width, (2) line density, (3) line edge quality/smoothness, (4) overspray (OS), (5) line discontinuity, and (6) internal connectivity. The experimentally observed line morphology trends as a function of ShGFR and CGFR were verified with computational fluid dynamics (CFD) simulations. The image-based line morphology quantifiers proposed in this work can be used for online detection of incipient process drifts, while the CFD model is valuable to ascertain the appropriate corrective action to bring the process back in control in case of a drift.

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References

Hon, K. , Li, L. , and Hutchings, I. , 2008, “ Direct Writing Technology—Advances and Developments,” CIRP Ann.-Manuf. Technol., 57(2), pp. 601–620. [CrossRef]
Hoey, J. M. , Lutfurakhmanov, A. , Schulz, D. L. , and Akhatov, I. S. , 2012, “ A Review on Aerosol-Based Direct-Write and Its Applications for Microelectronics,” J. Nanotechnol., 2012, p. 324380. [CrossRef]
Christenson, K. K. , Paulsen, J. A. , Renn, M. J. , McDonald, K. , and Bourassa, J. , 2011, “ Direct Printing of Circuit Boards Using Aerosol Jet,” 27th International Conference on Digital Printing Technologies (NIP27) & Digital Fabrication Conference, St. Paul, MN, Oct. 2–6, pp. 433–436.
Hedges, M. , and Marin, A. B. , 2012, “ 3D Aerosol Jet Printing-Adding Electronics Functionality to RP/RM,” The Fraunhofer Direct Digital Manufacturing Conference (DDMC), Berlin, Germany, Mar. 14–15, 2012, pp. 14–15.
Tait, J. G. , Witkowska, E. , Hirade, M. , Ke, T.-H. , Malinowski, P. E. , Steudel, S. , Adachi, C. , and Heremans, P. , 2015, “ Uniform Aerosol Jet Printed Polymer Lines With 30 μm Width for 140ppi Resolution RGB Organic Light Emitting Diodes,” Org. Electron., 22, pp. 40–43. [CrossRef]
Daniel, J. , 2010, “ Printed Electronics: Technologies, Challenges, and Applications,” International Workshop on Flexible Printed Electronics (IWFPE 10), Muju Resort, Korea, Sept. 8–10, pp. 8–10.
Jones, C. S. , Lu, X. , Renn, M. , Stroder, M. , and Shih, W.-S. , 2010, “ Aerosol-Jet-Printed, High-Speed, Flexible Thin-Film Transistor Made Using Single-Walled Carbon Nanotube Solution,” Microelectron. Eng., 87(3), pp. 434–437. [CrossRef]
Perez, K. B. , and Williams, C. B. , 2013, “ Combining Additive Manufacturing and Direct Write for Integrated Electronics—A Review,” International Solid Freeform Fabrication Symposium, Austin, TX, Aug. 12–14, 2013.
Perez, K. B. , and Williams, C. B. , 2014, “ Design Considerations for Hybridizing Additive Manufacturing and Direct Write Technologies,” ASME Paper No. DETC2014-35408, p. V004T06A005.
Xia, Y. , Zhang, W. , Ha, M. , Cho, J. H. , Renn, M. J. , Kim, C. H. , and Frisbie, C. D. , 2010, “ Printed Sub‐2 V Gel‐Electrolyte‐Gated Polymer Transistors and Circuits,” Adv. Funct. Mater., 20(4), pp. 587–594. [CrossRef]
Parekh, D. P. , Cormier, D. , and Dickey, M. D. , 2015, “ Multifunctional Printing: Incorporating Electronics Into 3D Parts Made by Additive Manufacturing,” Additive Manufacturing, A. Bandyopadhyay and S. Bose , eds., CRC Press, Boca Raton, FL, p. 215.
Ahn, B. Y. , and Lewis, J. A. , 2014, “ Amphiphilic Silver Particles for Conductive Inks With Controlled Wetting Behavior,” Mater. Chem. Phys., 148(3), pp. 686–691. [CrossRef]
Chou, J. , McAllister, M. , and Schottland, P. , 2014, “ Aerosol Jet Printable Metal Conductive Inks, Glass Coated Metal Conductive Inks and UV-Curable Dielectric Inks and Methods of Preparing and Printing the Same,” U.S. Patent No. 2014/0035995 A1.
King, B. , and Renn, M. , 2009, “ Aerosol Jet Direct Write Printing for Mil-Aero Electronic Applications,” Lockheed Martin Palo Alto Colloquia, Palo Alto, CA.
Seifert, T. , Baum, M. , Roscher, F. , Wiemer, M. , and Gessner, T. , 2015, “ Aerosol Jet Printing of Nano Particle Based Electrical Chip Interconnects,” Mater. Today: Proc., 2(8), pp. 4262–4271. [CrossRef]
Stoukatch, S. , Laurent, P. , Dricot, S. , Axisa, F. , Seronveaux, L. , Vandormael, D. , Beeckman, E. , Heusdens, B. , and Destiné, J. , 2012, “ Evaluation of Aerosol Jet Printing (AJP) Technology for Electronic Packaging and Interconnect Technique,” 4th Electronic System-Integration Technology Conference (ESTC), Amsterdam, The Netherlands, Sept. 17–20, pp. 1–5.
Wadhwa, A. , 2015, “ Run-Time Ink Stability in Pneumatic Aerosol Jet Printing Using a Split Stream Solvent Add Back System,” M.S. thesis, Advisor: Denis Cormier, Department of Industrial and Systems Engineering, Rochester Institute of Technology, Rochester, NY.
Mahajan, A. , Frisbie, C. D. , and Francis, L. F. , 2013, “ Optimization of Aerosol Jet Printing for High-Resolution, High-Aspect Ratio Silver Lines,” ACS Appl. Mater. Interfaces, 5(11), pp. 4856–4864. [CrossRef] [PubMed]
Paulsen, J. , Renn, M. , Christenson, K. , and Plourde, R. , 2012, “ Printing Conformal Electronics on 3D Structures With Aerosol Jet Technology,” Future of Instrumentation International Workshop (FIIW), Gatlinburg, TN, Oct. 8–9, pp. 1–4.
Blumenthal, T. , Fratello, V. , Nino, G. , and Ritala, K. , 2013, “ Conformal Printing of Sensors on 3D and Flexible Surfaces Using Aerosol Jet Deposition,” Proc. SPIE 8691, Nanosensors, Biosensors, and Info-Tech Sensors and Systems, San Diego, CA, Mar. 10–14, pp. 86910P–86919.
Jabari, E. , and Toyserkani, E. , 2015, “ Micro-Scale Aerosol-Jet Printing of Graphene Interconnects,” Carbon, 91, pp. 321–329. [CrossRef]
Navratil, J. , Hamacek, A. , Reboun, J. , and Soukup, R. , 2015, “ Perspective Methods of Creating Conductive Paths by Aerosol Jet Printing Technology,” 38th International Spring Seminar on Electronics Technology (ISSE), Eger, Hungary, May 6–10, pp. 36–39.
Rahman, T. , Renaud, L. , Heo, D. , Renn, M. , and Panat, R. , 2015, “ Aerosol Based Direct-Write Micro-Additive Fabrication Method for Sub-mm 3D Metal-Dielectric Structures,” J. Micromech. Microeng., 25(10), p. 107002. [CrossRef]
Robinson, M. J. , 2012, “ Experimental Characterization of Aerosol Flow through Micro-Capillaries,” M.S. thesis, Advisor: Iskander Akhatov, Department of Mechanical Engineering and Applied Mechanics, North Dakota State University, Fargo, ND.
Wang, F.-X. , Lin, J. , Gu, W.-B. , Liu, Y.-Q. , Wu, H.-D. , and Pan, G.-B. , 2013, “ Aerosol-Jet Printing of Nanowire Networks of Zinc Octaethylporphyrin and Its Application in Flexible Photodetectors,” Chem. Commun., 49(24), pp. 2433–2435. [CrossRef]
Wang, S.-W. , Lin, H.-Y. , Lin, C.-C. , Kao, T. S. , Chen, K.-J. , Han, H.-V. , Li, J.-R. , Lee, P.-T. , Chen, H.-M. , and Hong, M.-H. , 2016, “ Pulsed-Laser Micropatterned Quantum-Dot Array for White Light Source,” Sci. Rep., 6, p. 23563. [CrossRef] [PubMed]
Zhao, D. , Liu, T. , Zhang, M. , Chen, J.-M. , and Wang, B. , 2012, “ Nanotube-Enhanced Aerosol-Jet Printed Electronics for Embedded Sensing of Composite Structural Health,” Materials Research Society Proceedings, pp. mrsf11-1407–aa1415-1401.
Gao, W. , Zhang, Y. , Ramanujan, D. , Ramani, K. , Chen, Y. , Williams, C. B. , Wang, C. C. , Shin, Y. C. , Zhang, S. , and Zavattieri, P. D. , 2015, “ The Status, Challenges, and Future of Additive Manufacturing in Engineering,” Comput.-Aided Des., 69, pp. 65–89. [CrossRef]
Lee, G.-Y. , Park, J.-I. , Kim, C.-S. , Yoon, H.-S. , Yang, J. , and Ahn, S.-H. , 2014, “ Aerodynamically Focused Nanoparticle (AFN) Printing: Novel Direct Printing Technique of Solvent-Free and Inorganic Nanoparticles,” ACS Appl. Mater. Interfaces, 6(19), pp. 16466–16471. [CrossRef] [PubMed]
Mahajan, A. , Hyun, W. J. , Walker, S. B. , Lewis, J. A. , Francis, L. F. , and Frisbie, C. D. , 2015, “ High-Resolution, High-Aspect Ratio Conductive Wires Embedded in Plastic Substrates,” ACS Appl. Mater. Interfaces, 7(3), pp. 1841–1847. [CrossRef] [PubMed]
Seifert, T. , Sowade, E. , Roscher, F. , Wiemer, M. , Gessner, T. , and Baumann, R. R. , 2015, “ Additive Manufacturing Technologies Compared: Morphology of Deposits of Silver Ink Using Inkjet and Aerosol Jet Printing,” Ind. Eng. Chem. Res., 54(2), pp. 769–779. [CrossRef]
Verheecke, W. , Van Dyck, M. , Vogeler, F. , Voet, A. , and Valkenaers, H. , 2012, “ Optimizing Aerosol Jet Printing of Silver Interconnects on Polyimide Film for Embedded Electronics Applications,” 8th International Danube Adria Association for Automation and Manufacturing Baltic Conference “Industrial Engineering,” Tallinn, Estonia, Apr. 19–21, pp. 373–379.
Vogeler, F. , Verheecke, W. , Voet, A. , and Valkenaers, H. , 2013, “ An Initial Study Into Aerosol Jet Printed Interconnections on Extrusion Based 3D Printed Substrates,” Strojniski Vestn.-J. Mech. Eng., 59(11), pp. 689–696. [CrossRef]
Schulz, D. , Hoey, J. , Thompson, D. , Swenson, O. , Han, S. , Lovaasen, J. , Dai, X. , Braun, C. , Keller, K. , and Akhatov, I. , 2010, “ Collimated Aerosol Beam Deposition: Sub 5-μm Resolution of Printed Actives and Passives,” IEEE Transactions on Advanced Packaging, 33(2), pp. 421–427.
Akhatov, I. , Hoey, J. , Swenson, O. , and Schulz, D. , 2008, “ Aerosol Focusing in Micro-Capillaries: Theory and Experiment,” J. Aerosol Sci., 39(8), pp. 691–709. [CrossRef]
Akhatov, I. , Hoey, J. , Swenson, O. , and Schulz, D. , 2008, “ Aerosol Flow Through a Long Micro-Capillary: Collimated Aerosol Beam,” Microfluid. Nanofluid., 5(2), pp. 215–224. [CrossRef]
Akhatov, I. S. , Hoey, J. M. , Thompson, D. , Lutfurakhmanov, A. , Mahmud, Z. , Swenson, O. F. , Schulz, D. L. , and Osiptsov, A. N. , 2009, “ Aerosol Flow Through a Micro-Capillary,” ASME Paper No. MNHMT2009-18421, pp. 223–232.
Feng, J. Q. , 2016, “ A Computational Study of High-Speed Microdroplet Impact Onto a Smooth Solid Surface,” Phys.-Fluid Dyn., epub, arXiv.org, Cornell University Library, Cornell, NY.
Feng, J. Q. , 2015, “ Sessile Drop Deformations Under an Impinging Jet,” Theor. Comput. Fluid Dyn., 29(4), pp. 277–290. [CrossRef]
McCormack, B. , 1992, “ Test Coupons as an Aid to Process Control of the PCB Manufacturing and Assembly Processes,” Circuit World, 18(3), pp. 17–20. [CrossRef]
King, B. H. , 2014, “ Miniature Aerosol Jet and Aerosol Jet Array,” U.S. Patent No. 8640975 B2.
Park, J. , Jeong, J. , Kim, C. , and Hwang, J. , 2013, “ Deposition of Charged Aerosol Particles on a Substrate by Collimating through an Electric Field Assisted Coaxial Flow Nozzle,” Aerosol Sci. Technol., 47(5), pp. 512–519. [CrossRef]
Eckstein, R. , Hernandez-Sosa, G. , Lemmer, U. , and Mechau, N. , 2014, “ Aerosol Jet Printed Top Grids for Organic Optoelectronic Devices,” Org. Electron., 15(9), pp. 2135–2140. [CrossRef]
Shin, D.-Y. , Seo, J.-Y. , Tak, H. , and Byun, D. , 2015, “ Bimodally Dispersed Silver Paste for the Metallization of a Crystalline Silicon Solar Cell Using Electrohydrodynamic Jet Printing,” Sol. Energy Mater. Sol. Cells, 136, pp. 148–156. [CrossRef]
Pletcher, R. H. , Tannehill, J. C. , and Anderson, D. , 2012, Computational Fluid Mechanics and Heat Transfer, 3rd ed., CRC Press, Boca Raton, FL.
Versteeg, H. K. , and Malalasekera, W. , 2007, An Introduction to Computational Fluid Dynamics: The Finite Volume Method, 2nd ed., Pearson Education in South Asia, Noida, India.
Brennen, C. E. , 2005, Fundamentals of Multiphase Flow, Cambridge University Press, New York.
Crowe, C. T. , Schwarzkopf, J. D. , Sommerfeld, M. , and Tsuji, Y. , 2011, Multiphase Flows With Droplets and Particles, 2nd ed., CRC Press, Boca Raton, FL.
ANSYS-Fluent, 2012, “ 14.5 Theory Guide,” ANSYS, Canonsburg, PA.
Morsi, S. , and Alexander, A. , 1972, “ An Investigation of Particle Trajectories in Two-Phase Flow Systems,” J. Fluid Mech., 55(2), pp. 193–208. [CrossRef]
Marshall, J. , 2009, “ Discrete-Element Modeling of Particulate Aerosol Flows,” J. Comput. Phys., 228(5), pp. 1541–1561. [CrossRef]
Canuto, C. G. , Hussaini, M. Y. , Quarteroni, A. M. , and Zang, T. A. , 2007, Spectral Methods: Evolution to Complex Geometries and Applications to Fluid Dynamics (Scientific Computation), 1st ed., Springer-Verlag, Berlin/Heidelberg, Germany.
Nixon, M. , 2008, Feature Extraction & Image Processing for Computer Vision, 3rd ed., Academic Press (Elsevier), London, UK.
Aström, K. J. , and Murray, R. M. , 2010, Feedback Systems: An Introduction for Scientists and Engineers, Princeton University Press, Princeton, NJ.
Wescott, T. , 2011, Applied Control Theory for Embedded Systems, Newnes (Elsevier), Burlington, MA.
Hoerber, J. , Goth, C. , Franke, J. , and Hedges, M. , 2011, “ Electrical Functionalization of Thermoplastic Materials by Aerosol Jet Printing,” 13th Institute of Electrical and Electronics Engineers Electronics Packaging Technology Conference (EPTC), Singapore, Dec. 7–9, pp. 813–818.
Liu, R. , Shen, F. , Ding, H. , Lin, J. , Gu, W. , Cui, Z. , and Zhang, T. , 2013, “ All-Carbon-Based Field Effect Transistors Fabricated by Aerosol Jet Printing on Flexible Substrates,” J. Micromech. Microeng., 23(6), p. 065027. [CrossRef]
Rao, P. K. , Beyca, O. F. , Kong, Z. , Bukkaptanam, S. T. , Case, K. E. , and Komanduri, R. , 2015, “ A Graph Theoretic Approach for Quantification of Surface Morphology and Its Application to Chemical Mechanical Planarization (CMP) Process,” IIE Trans., 47(10), pp. 1088–1111. [CrossRef]
Rao, P. K. , Kong, Z. , Duty, C. E. , Smith, R. J. , Kunc, V. , and Love, L. J. , 2016, “ Assessment of Dimensional Integrity and Spatial Defect Localization in Additive Manufacturing Using Spectral Graph Theory,” ASME J. Manuf. Sci. Eng., 138(5), p. 051007. [CrossRef]
Lappa, M. , 2009, Thermal Convection: Patterns, Evolution and Stability, 1st ed., Wiley, West Sussex, UK.
Estellers, V. , Thiran, J.-P. , and Gabrani, M. , 2014, “ Surface Reconstruction from Microscopic Images in Optical Lithography,” IEEE Trans. Image Process., 23(8), pp. 3560–3573. [CrossRef] [PubMed]
Zhang, C. , Huang, P. S. , and Chiang, F.-P. , 2002, “ Microscopic Phase-Shifting Profilometry Based on Digital Micromirror Device Technology,” Appl. Opt., 41(28), pp. 5896–5904. [CrossRef] [PubMed]

Figures

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Fig. 1

(a)–(c) Offline images of AJP-printed electronic traces captured by an optical microscope (Carl Zeiss M1M); (d)–(f) online images captured by a high-resolution CCD color camera installed on our experimental setup

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Fig. 2

(a)–(c) Offline 3D profilometry images showing the line thickness profile taken with an optical profilometer (Wyko NT-1100)

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Fig. 3

Electronic devices and structures AJP-printed at the authors' facilities in Binghamton University. (a) An antenna printed on a flexible glass substrate; (b) reduced graphene oxide (rGO) supercapacitors (SCs) and silver interdigitated electrodes (IDEs) printed on a slim glass substrate; (c) silver test lines printed on a polymer substrate; and (d) silver interdigitated electrodes (IDEs) printed on polyimide.

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Fig. 4

A list of material, machine, and process factors influencing the morphology and functional integrity of an AJP-printed line

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Fig. 5

Different situations where line morphology deviates (drifts) from the target, stemming from complex materials, process, and machine interactions. (The images have been inverted and thresholded to binary equivalents.)

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Fig. 6

(a) and (b) Pictures and (c) a schematic diagram of the experiential setup showing the imaging components installed on the Optomec AJ-300 system

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Fig. 7

(a) The main components of the deposition head. (b) The deposition head assembly. A cross-sectional view of the deposition head and (c) obtained using X-ray computed tomography.

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Fig. 8

The Reynolds number as a function of ShGFR showing that the internal flow remains laminar both in the combination chamber and at the nozzle exit. A laminar viscous model was chosen as a result.

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Fig. 9

A free body diagram showing the forces acting on a particle in a shear flow. u is the carrier flow velocity vector, v is the particle velocity vector, and ωd is the particle rotation vector.

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Fig. 10

The four types of boundary defined for each zone of the problem modeled in the ansys-fluent environment

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Fig. 11

(a) The zones of background (BG), overspray (OS), and line width (LW) detected based on two spatial threshold parameters (obtained using a threshold estimator, proposed in this study). (b) The one-dimensionalized intensity profile of the image shown in part (a). (c) The first derivative of the intensity profile indicating the approximate range of each zone based on which the threshold parameters (as reference intensities) as well as the coordinates of the threshold lines (shown in Fig. 12) are determined.

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Fig. 12

Visual representation of the morphology quantifiers proposed in this study. Line width (LW): the average distance between the upper and lower edges (shown as two solid lines); line density (Lρ): the average intensity of all pixels constituting the line; edge quality (LEQ): the inverse, average distance between each edge and its corresponding threshold line (shown as two dashed lines); overspray (LOS): The weighted, average distance between each overspray pixel and its corresponding line edge multiplied by the intensity; line discontinuity (LDisc): the average number of failures in the edge detection. The image is read from top to bottom.

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Fig. 13

The effect of the sheath gas flow rate (ShGFR) on line morphology. The carrier gas flow rate (CGFR) and print speed (Ps) were fixed at 30 sccm and 1 mm/s, respectively.

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Fig. 14

The line morphology features captured using the six quantifiers proposed in this study. The error bars are (±1 σ/n) long where n equals the number of replications (10). The secondary abscissa tracks the corresponding sheath gas flow pressure (ShGFP).

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Fig. 15

A comparison between the online and offline experimental results versus ShGFR, signifying the consistency between the two methods. The error bars are (±1 σ/n) long where n equals the number of replications (10). Capturing the same trend for each morphology attribute, the online and offline quantifiers were plotted on two axes to offset the difference arising from different image properties.

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Fig. 16

The changes in line morphology as a function of ShGFR, employing the pneumatic atomizer. The lines are of Paru PG-007 Ag ink printed on a Ube UPILEX-75 S polyimide film.

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Fig. 17

A comparison between the ultrasonic and pneumatic experimental results of line morphology versus ShGFR, corroborating the consistency of trends between the two atomization techniques. The error bars are (±1 σ/n) long where n (=10) equals the number of replications.

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Fig. 18

(a) The influence of ShGFR on line width (left axis) and on the aerosol jet width (right axis); (b) the influence of ShGFR on the carrier flow deposition spread (right axis) and on the internal connectivity of the lines, represented by Fiedler number (left axis). (c) Plot of the Reynolds number versus ShGFR indicating that the aerosol flow in the combination chamber becomes hydrodynamically instable when the ShGFR ≥ 100 sccm (i.e., Re ∼ 950) [60]. The error bars are (±1 σ/n) long where n equals the number of replications (10). An empirical geometry factor of 6 was used to scale the 2D-CFD simulation to the 3D experimental data.

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Fig. 19

The influence of increasing ShGFR on the flow velocity profile and on the particle trajectory (a) and (b): in the combination chamber and (c) and (d): during the deposition

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Fig. 20

The influence of ShGFR on the flow pressure profile as well as on the trajectory of particles in the combination chamber. The ShGFR of 80 sccm seems to be the onset of pressure buildup in the chamber. Hence, the maximum pressure limit can be considered approximately 622 Pa. In this simulation, the carrier gas flow rate (CGFR) was set at 30 sccm.

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Fig. 21

(a)–(f) The effect of the carrier gas flow rate (CGFR) on line morphology, both the sheath gas flow rate (ShGFR) and print speed (PS) were fixed at 60 sccm and 1 mm/s, respectively

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Fig. 22

The main features of the line morphology as a function of the CGFR captured using the quantifiers developed in this study. The error bars are (±1 σ/n) long where n equals the number of replications (10). The secondary abscissa tracks the corresponding carrier gas flow pressure (CGFP, Pa).

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Fig. 23

A comparison between the online and offline experimental results versus the CGFR, signifying the consistency between the two methods. The error bars are (±1 σ/n) long where n equals the number of replications (10). Capturing the same trend for each morphology attribute, the online and offline quantifiers were plotted on two axes to offset the difference arising from different image properties.

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Fig. 24

The influence of the CGFR on the line width (left axis) and on the aerosol jet width (right axis). The error bars are (±1 σ/n) long where n equals the number of replications (10). The objective was to show the model could capture the same trend as the experiment; a geometry factor of 6 was used for scaling the CFD simulation results to the experimental observations.

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Fig. 25

The influence of increasing CGFR on the flow velocity profile and on the particle trajectory (a) and (b): in the combination chamber and (c) and (d) during the deposition process. In this simulation, the sheath gas flow rate (ShGFR) was set at 60 sccm.

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Fig. 26

The proposed stereomicroscopy-based approach, which will be used to quantify line thickness in our future work. (a) A picture of the experimental setup equipped with a stereomicroscope; (b) and (c) the left and right views of a printed line, respectively. The line thickness is quantified based on the two perspective views.

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Fig. 27

The influence of print speed (PS) on line morphology. The edge quality and line width are more significantly affected than the other morphology features (developed in Sec. 4).

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Fig. 28

The line morphology features captured using the quantifiers developed in this study. The error bars are (±1 σ/n) long where n equals the number of replications (n = 10).

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