{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,20]],"date-time":"2025-11-20T12:30:34Z","timestamp":1763641834870,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2014,9,1]],"date-time":"2014-09-01T00:00:00Z","timestamp":1409529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This paper reports the numerical and experimental analysis of the acoustic streaming effect in a fluidic domain. The actuation of a piezoelectric transducer generates acoustic waves that propagate to the fluids, generating pressure gradients that induce the flow. The number and positioning of the transducers affect the pressure gradients and, consequently, the resultant flow profile. Two actuation conditions were considered:  (1) acoustic streaming generated by a 28 \u03bcm thick \u03b2-poly(vinylidene fluoride) (\u03b2-PVDF) piezoelectric transducer placed asymmetrically relative to the fluidic domain and (2) acoustic streaming generated by two 28 \u03bcm thick \u03b2-PVDF piezoelectric transducers placed perpendicularly to each other. The transducers were fixed to the lower left corner of a poly(methyl methacrylate) (PMMA)cuvette and were actuated with a 24 Vpp and 34.2 MHz sinusoidal voltage. The results show that the number of transducers and their positioning affects the shape and number of recirculation areas in the acoustic streaming flows. The obtained global flows show great potential for mixing and pumping, being an alternative to the previous geometries studied by the authors, namely, a single transducer placed symmetrically under a fluidic domain.<\/jats:p>","DOI":"10.3390\/mi5030654","type":"journal-article","created":{"date-parts":[[2014,9,1]],"date-time":"2014-09-01T10:03:19Z","timestamp":1409565799000},"page":"654-666","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Effect of \u03b2-PVDF Piezoelectric Transducers\u2019 Positioning on the Acoustic Streaming Flows"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8962-0710","authenticated-orcid":false,"given":"Susana","family":"Catarino","sequence":"first","affiliation":[{"name":"Transport Phenomena Research Center, Department of Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"},{"name":"Centro Algoritmi, University of Minho, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"}]},{"given":"Jo\u00e3o","family":"Miranda","sequence":"additional","affiliation":[{"name":"Transport Phenomena Research Center, Department of Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2460-0556","authenticated-orcid":false,"given":"Gra\u00e7a","family":"Minas","sequence":"additional","affiliation":[{"name":"Centro Algoritmi, University of Minho, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2014,9,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"82","DOI":"10.3390\/mi1030082","article-title":"A review on mixing in microfluidics","volume":"1","author":"Suh","year":"2010","journal-title":"Micromachines"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/S0924-4247(00)00433-7","article-title":"Miniature valveless ultrasonic pumps and mixers","volume":"86","author":"Rife","year":"2000","journal-title":"Sensors Actuators A Phys."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1007\/s00791-006-0040-y","article-title":"Numerical simulation of piezoelectrically agitated surface acoustic waves on microfluidic biochips","volume":"10","author":"Gantner","year":"2006","journal-title":"Comput. Vis. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1016\/j.apacoust.2004.03.005","article-title":"Acoustic streaming in micro-scale cylindrical channels","volume":"65","author":"Frampton","year":"2004","journal-title":"Appl. Acoust."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1463","DOI":"10.1109\/58.883536","article-title":"Acoustic streaming in micromachined flexural plate wave devices: Numerical simulation and experimental verification","volume":"47","author":"Nguyen","year":"2000","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1146\/annurev-fluid-010313-141418","article-title":"Surface acoustic wave microfluidics","volume":"46","author":"Yeo","year":"2014","journal-title":"Annu. Rev. Fluid Mech."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2438","DOI":"10.1039\/c2lc40203c","article-title":"Acoustofluidics 14: Applications of acoustic streaming in microfluidic devices","volume":"12","author":"Wiklund","year":"2012","journal-title":"Lab Chip"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/S0925-4005(03)00521-5","article-title":"A fully polymeric micropump with piezoelectric actuator","volume":"97","author":"Nguyen","year":"2004","journal-title":"Sensors Actuators B Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2352","DOI":"10.1137\/060676623","article-title":"Numerical simulation of acoustic streaming on surface acoustic wave-driven biochips","volume":"29","year":"2007","journal-title":"SIAM J. Sci. Comput."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"773","DOI":"10.1039\/C2LC21065G","article-title":"Uniform mixing in paper-based microfluidic systems using surface acoustic waves","volume":"12","author":"Rezk","year":"2012","journal-title":"Lab Chip"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1007\/s001620050068","article-title":"Acoustic streaming","volume":"10","author":"Riley","year":"1998","journal-title":"Theor. Comput. Fluid Dyn."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1146\/annurev.fluid.33.1.43","article-title":"Steady streaming","volume":"33","author":"Riley","year":"2001","journal-title":"Annu. Rev. Fluid Mech."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1121\/1.1907010","article-title":"Acoustic streaming due to attenuated plane waves","volume":"25","author":"Nyborg","year":"1953","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2226","DOI":"10.1016\/j.jnoncrysol.2006.02.052","article-title":"Processing and characterization of a novel nonporous poly(vinilidene fluoride) films in the \u03b2 phase","volume":"352","author":"Sencadas","year":"2006","journal-title":"J. Non. Cryst. Solids"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1080\/00150190390238621","article-title":"Mechanical characterization and influence of the high temperature shrinkage of \u03b2-PVDF films on its electromechanical properties","volume":"294","author":"Sencadas","year":"2003","journal-title":"Ferroelectrics"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1184","DOI":"10.1109\/TBME.2009.2035054","article-title":"Lab-on-a-chip with \u03b2-poly(vinylidene fluoride) based acoustic microagitation","volume":"57","author":"Cardoso","year":"2010","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Bar-Cohen, Y. (2004). Electroactive Polymer (EAP) Actuators as Artificial Muscles: Reality, Potential and Challenges, SPIE Press Book. [2nd ed.].","DOI":"10.1117\/3.547465"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"033001","DOI":"10.1088\/0964-1726\/23\/3\/033001","article-title":"A review of piezoelectric polymers as functional materials for electromechanical transducers","volume":"23","author":"Ramadan","year":"2014","journal-title":"Smart Mater. Struct."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"087002","DOI":"10.1088\/0964-1726\/20\/8\/087002","article-title":"Micro and nanofilms of poly(vinylidene fluoride) with controlled thickness, morphology and electroactive crystalline phase for sensor and actuator applications","volume":"20","author":"Cardoso","year":"2011","journal-title":"Smart Mater. Struct."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1103\/PhysRev.73.68","article-title":"Vortices and streams caused by sound waves","volume":"73","author":"Eckart","year":"1948","journal-title":"Phys. Rev."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1565","DOI":"10.1016\/j.snb.2011.09.007","article-title":"Quantification of surface acoustic wave induced chaotic mixing-flows in microfluidic wells","volume":"160","author":"Shilton","year":"2011","journal-title":"Sensors Actuators B Chem."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"619","DOI":"10.1007\/s10404-010-0694-0","article-title":"High-throughput micromixers based on acoustic streaming induced by surface acoustic wave","volume":"10","author":"Luong","year":"2010","journal-title":"Microfluid. Nanofluid."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1016\/j.apacoust.2009.08.002","article-title":"A standing wave model for acoustic pumping effect in microchannels","volume":"71","author":"Huang","year":"2010","journal-title":"Appl. Acoust."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2738","DOI":"10.1039\/b903687c","article-title":"A millisecond micromixer via single-bubble-based acoustic streaming","volume":"9","author":"Ahmed","year":"2009","journal-title":"Lab Chip"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Catarino, S.O., Miranda, J.M., Lanceros-M\u00e9ndez, S., and Minas, G. (2014). Numerical prediction of acoustic streaming in a microcuvete. Can. J. Chem. Eng.","DOI":"10.1002\/cjce.22057"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"012091","DOI":"10.1088\/1742-6596\/395\/1\/012091","article-title":"A numerical study on the heat transfer generated by a piezoelectric transducer in a microfluidic system","volume":"395","author":"Catarino","year":"2012","journal-title":"J. Phys. Conf. Ser."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"681","DOI":"10.1016\/S0003-682X(03)00005-7","article-title":"The scaling of acoustic streaming for application in micro-fluidic devices","volume":"64","author":"Frampton","year":"2003","journal-title":"Appl. Acoust."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1016\/S0924-4247(99)00216-2","article-title":"Design and optimization of an ultrasonic flexural plate wave micropump using numerical simulation","volume":"77","author":"Nguyen","year":"1999","journal-title":"Sensors Actuators A Phys."},{"key":"ref_29","unstructured":"Pozar, D. (2005). Microwave Engineering, John Wiley & Sons. [3rd ed.]."},{"key":"ref_30","unstructured":"Thielicke, W., and Stamhuis, E.J. PIVlab\u2014Time-Resolved Digital Particle Image Velocimetry Tool for MATLAB (version: 1.32). Available online:http:\/\/figshare.com\/articles\/PIVlab_version_1_35\/1092508."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Catarino, S.O., Silva, L.R., Mendes, P.M., Miranda, J.M., Lanceros-Mendez, S., and Minas, G. (2014). Piezoelectric actuators for acoustic mixing in microfluidic devices numerical prediction and experimental validation of heat and mass transport. Sensors Actuators B Chem.","DOI":"10.1016\/j.snb.2014.08.030"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"183505","DOI":"10.1063\/1.2374683","article-title":"Acoustic streaming pattern induced by longitudinal ultrasonic vibration in an open channel using particle imaging velocimetry","volume":"89","author":"Loh","year":"2006","journal-title":"Appl. Phys. Lett."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/5\/3\/654\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:15:27Z","timestamp":1760217327000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/5\/3\/654"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,9,1]]},"references-count":32,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2014,9]]}},"alternative-id":["mi5030654"],"URL":"https:\/\/doi.org\/10.3390\/mi5030654","relation":{},"ISSN":["2072-666X"],"issn-type":[{"type":"electronic","value":"2072-666X"}],"subject":[],"published":{"date-parts":[[2014,9,1]]}}}