Micropropulsion and microrheology in complex fluids via symmetry breaking
2012 (English)In: Physics of fluids, ISSN 1070-6631, E-ISSN 1089-7666, Vol. 24, no 10, 103102- p.Article in journal (Refereed) Published
Many biological fluids have polymeric microstructures and display non-Newtonian rheology. We take advantage of such nonlinear fluid behavior and combine it with geometrical symmetry-breaking to design a novel small-scale propeller able to move only in complex fluids. Its propulsion characteristics are explored numerically in an Oldroyd-B fluid for finite Deborah numbers while the small Deborah number limit is investigated analytically using a second-order fluid model. We then derive expressions relating the propulsion speed to the rheological properties of the complex fluid, allowing thus to infer the normal stress coefficients in the fluid from the locomotion of the propeller. Our simple mechanism can therefore be used either as a non-Newtonian micro-propeller or as a micro-rheometer.
Place, publisher, year, edition, pages
2012. Vol. 24, no 10, 103102- p.
Biological fluids, Complex fluids, Deborah numbers, Micro propulsion, Micro-rheometers, Microrheology, Non-newtonian, Non-Newtonian rheology, Nonlinear fluids, Normal stress, Oldroyd-B fluid, Polymeric microstructures, Propulsion characteristics, Rheological property, Second-order fluids, Symmetry-breaking
IdentifiersURN: urn:nbn:se:kth:diva-96941DOI: 10.1063/1.4758811ISI: 000310595100021ScopusID: 2-s2.0-84868629219OAI: oai:DiVA.org:kth-96941DiVA: diva2:533286
FunderSwedish e‐Science Research Center
QC 20121205. Updated from submitted to published.2012-06-132012-06-132014-03-13Bibliographically approved