English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The dispersed phase in turbulence can vary from almost inviscid fluid tohighly viscous fluid. By changing the viscosity of the dispersed droplet phase,we experimentally investigate how the deformability of dispersed dropletsaffects the global transport quantity of the turbulent emulsion. Differentkinds of silicone oil are employed to result in the viscosity ratio, $\zeta$,ranging from $0.53$ to $8.02$. The droplet volume fraction, $\phi$, is variedfrom 0\% to 10\% with a spacing of 2\%. The global transport quantity,quantified by the normalized friction coefficient $c_{f,\phi}/c_{f,\phi=0}$,shows a weak dependence on the turbulent intensity due to the vanishingfinite-size effect of the droplets. The interesting fact is that, withincreasing $\zeta$, the $c_{f,\phi}/c_{f,\phi=0}$ first increases and thensaturates to a plateau value which is similar to that of the rigid particlesuspension. By performing image analysis, this drag modification is interpretedfrom the aspect of droplet deformability, which is responsible for the breakupand coalescence effect of the droplets. The statistics of the droplet sizedistribution show that, with increasing $\zeta$, the stabilizing effect inducedby interfacial tension comes to be substantial and the pure inertial breakupprocess becomes dominant. The measurement of the droplet distribution along theradial direction of the system shows a bulk-clustering effect, which can beattributed to the non-negligible coalescence effect of the droplet. It is foundthat the droplet coalescence effect could be suppressed as the $\zeta$increases, thereby affecting the contribution of interfacial tension to thetotal stress, and accounting for the observed emulsion rheology.

Turbulence drag modulation by dispersed droplets in Taylor-Couette flow: the effects of the dispersed phase viscosity