title: Two-dimensional manipulation of micro particles by acoustic radiation pressure in a heptagon cell.
abstract: An acoustic particle manipulation system is presented, using a flexible printed circuit board formed into a regular heptagon. It is operated at 4 MHz and has a side dimension of 10 mm. The heptagonal geometry was selected for its asymmetry, which tends to reduce standing wave behavior. This leads to the possibility of having fine control over the acoustic field by varying the output phases of the transducer elements. Configurations with two and three active transducers are demonstrated experimentally. It is shown that with two transducers, the particles align along straight lines, the position of which can be moved by varying the relative excitation phases of the two transducers. With three active transducers, hexagonal-shaped patterns are obtained that can also be moved, again according to the phase of the excitation signals. Huygens' principle-based simulations were used to investigate the resultant pressure distributions. Good agreement was achieved between these simulations and both Schlieren imaging and particle manipulation observations.
authors: School of Engineering, University of Glasgow, Glasgow, UK. Anne.Bernassau@glasgow.ac.uk
authors: Anne L
authors: AL
authors: Bernassau
authors: Chun-Kiat
authors: CK
authors: Ong
authors: Yong
authors: Y
authors: Ma
authors: Peter G A
authors: PG
authors: MacPherson
authors: Charles R P
authors: CR
authors: Courtney
authors: Mathis
authors: M
authors: Riehle
authors: Bruce W
authors: BW
authors: Drinkwater
authors: David R S
authors: DR
authors: Cumming
mesh_terms: D000162:Acoustics; D003198:Computer Simulation; D004867:Equipment Design; D007854:Lead / Q000737:chemistry; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods*; D008863:Microspheres; D014025:Titanium / Q000737:chemistry; D014159:Transducers; D015040:Zirconium / Q000737:chemistry
chemical_list: C065536:lead titanate zirconate; D007854:Lead; D015040:Zirconium; D014025:Titanium