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Self-sustained biphasic catalytic particle turbulence.

ABSTRACT: Turbulence is known for its ability to vigorously mix fluid and transport heat. Despite over a century of research for enhancing heat transport, few have exceeded the inherent limits posed by turbulent-mixing. Here we have conceptualized a kind of "active particle" turbulence, which far exceeds the limits of classical thermal turbulence. By adding a minute concentration (?_v???1%) of a heavy liquid (hydrofluoroether) to a water-based turbulent convection system, a remarkably efficient biphasic dynamics is born, which supersedes turbulent heat transport by up to 500%. The system operates on a self-sustained dynamically equilibrated cycle of a "catalyst-like" species, and exploits several heat-carrier agents including pseudo-turbulence, latent heat and bidirectional wake capture. We find that the heat transfer enhancement is dominated by the kinematics of the active elements and their induced-agitation. The present finding opens the door towards the establishment of tunable, ultra-high efficiency heat transfer/mixing systems.

SUBMITTER: Wang Z

PROVIDER: S-EPMC6659658 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Self-sustained biphasic catalytic particle turbulence.

Wang Ziqi Z Mathai Varghese V Sun Chao C

Nature communications 20190726 1

Turbulence is known for its ability to vigorously mix fluid and transport heat. Despite over a century of research for enhancing heat transport, few have exceeded the inherent limits posed by turbulent-mixing. Here we have conceptualized a kind of "active particle" turbulence, which far exceeds the limits of classical thermal turbulence. By adding a minute concentration (ϕ<sub>v</sub> ∼ 1%) of a heavy liquid (hydrofluoroether) to a water-based turbulent convection system, a remarkably efficient ...[more]

PMID: 31350393

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