Numerical modeling of dielectrophoresis
2006 (English)Licentiate thesis, comprehensive summary (Other scientific)
We investigate the dielectrophoretic separation of microparticles. Two different models are formulated in two characteristic time scales. The first model mainly accounts for the orientation behavior and rotational motion of non-spheric microparticles. The concept of effective charge is suggested to calculate the finite size non-spheric particles. It is combined with the fluid particle dynamics method to calculate hydrodynamic as well as dielectrophoretic forces and torques. The translational motion and the particle-particle interaction are calculated also, but they take much longer time to be observed due to the different time scales of the rotational and translational motions By viewing the particle as spheres, the second model focus on the translational motion of spheres. The hydrodynamic force between particles and particle-particle electrostatic interactions are also taken into account. We check the relative magnitude ratio between these forces in order to determine the importance of these forces. To predict and guide the design of experimental dielectrophoretic separation, two numerical applications are carried out. The first calculation suggests optimum patterns to improve the trapping efficiency of E.coli. cells by applying superimposed AC electric fields. The second calculation finds out the mobility and separation rate of particles which differs in size and electric properties by a multi-step trapping-releasing strategy.
Place, publisher, year, edition, pages
Stockholm: KTH , 2006. , viii, 34 p.
Trita-MEK, ISSN 0348-467X ; 2006:14
dielectrophoresis, orientation of rotation, fluid particle dynamics, microparticle, molecular dynamics, hydrodynamics, particle-particle interaction, superimposed, mobility
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-4014OAI: oai:DiVA.org:kth-4014DiVA: diva2:10394
2006-06-06, Sal D3, KTH, Lindstedtsvägen 5, Stockholm, 13:00
Runborg, Olof, Docent
QC 201011182006-06-012006-06-012010-11-18Bibliographically approved
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