Capillary Pumping Independent Of Liquid Sample Viscosity [Elektronisk resurs]

• Capillary flow is a dominating liquid transport phenomenon on the micro- and nanoscale. As described at the beginning of the 20th century, the flow rate during imbibition of a horizontal capillary tube follows the Washburn equation, i.e. decreases over time and depends on the viscosity of the sample. This poses a problem for capillary driven systems that rely on a predictable flow rate and where the liquid viscosity is not precisely known. Here we introduce and successfully experimentally verify the first compact capillary pump design with a flow rate constant in time and independent of the liquid viscosity that can operate over an extended period of time. We also present a detailed theoretical model for gravitation independent capillary filling, which predicts the novel pump performance to within measurement error margins, and in which we, for the first time, explicitly identify gas inertia dominated flow as a fourth distinct flow regime in capillary pumping. These results are of potential interest for a multitude of applications and we expect our results to find most immediate applications within lab-on-a-chip systems and diagnostic devices. 

Ämnesord

Engineering and Technology  (hsv)

Teknik och teknologier  (hsv)

Teknisk mekanik  (kth)

Engineering Mechanics  (kth)

Genre

government publication  (marcgt)

Indexterm och SAB-rubrik

capillary pump viscosity independent