Experimental and numerical study of the recirculation flow inside a liquid meniscus focused by air

The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous...

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Detalhes bibliográficos
Autores: Gañán-Calvo, Alfonso M., Ferrera, C., Torregrosa, M., Herrada Gutiérrez, Miguel Ángel, Marchand, M.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:España
Recursos:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/102521
Acesso em linha:https://hdl.handle.net/11441/102521
https://doi.org/10.1007/s10404-011-0774-9
Access Level:acceso abierto
Palavra-chave:Cone-jet mode
Flow focusing
Flow structure visualization
Recirculating cell
Descrição
Resumo:The internal motions inside a liquid meniscus in the so-called liquid cone-jet mode, which can occur upon stimulation by a coflowing gas sheath in flow focusing, are explored by both numerical simulation and experimental visualization. The results for low viscosity liquids show that, as in previous numerical simulations, a recirculating cell inside the meniscus appears when the injected liquid flow rate is reduced. Thus, as the flow rate is reduced not only the average residence time of particles in the meniscus becomes longer, but the appearance of a recirculation cell provides a natural platform for the efficient micro-mixing of different species before they are ejected through the issuing jet. The numerical results were confirmed with experimental visualization of the flow inside the meniscus using a dyed liquid. However, when the viscosity of the liquid is increased the recirculating cell disappears. In this case, viscous stresses organize the streamlines and direct the flow to the meniscus tip, which prevents the recirculating cell from being formed even for very small injected rate of liquid flow.