Heat-transfer enhancement by adaptive reorientation of flow fields

Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review

Abstract

Scope is enhancement of scalar transport (heat, chemical species) in engineered flow systems by reorientations of a laminar base flow. Practical applications include mixing in inline heat exchangers by downstream reorientation of baffles, stirring in bio-reactors by cyclic repositioning of impellers, and subsurface chemicals distribution for in situ minerals mining by unsteady pumping schemes. Conventional reorientation schemes consist of a periodic reorientation (in space or time) of the flow designed to accomplish efficient fluid mixing. However, whether this approach indeed yields optimal scalar transport for significant diffusion and/or chemical reactions is unclear. The present study explores an alternative approach: adaptive reorientation of the flow by interval-wise selection of the reorientation that is predicted to yield optimal scalar transport for a future time horizon. Key enabler for fast predictions is a compact model based on the spectral decomposition of the scalar evolution in the base
flow. The adaptive reorientation scheme is investigated for a representative problem: enhanced heating of a cold fluid in a 2D circular domain by an unsteady flow driven by step-wise activation of moving boundary segments. This reveals that the adaptive reorientation scheme can substantially accelerate
the heating compared to conventional time-periodic reorientation designed for efficient mixing and thus demonstrates its potential for attaining optimal scalar transport in reoriented flows.
LanguageEnglish
Title of host publicationProceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA
StateAccepted/In press - 2020
Event5th Thermal and Fluids Engineering Conference (TFEC) - New Orleans, United States
Duration: 5 Apr 20208 Apr 2020

Conference

Conference5th Thermal and Fluids Engineering Conference (TFEC)
CountryUnited States
CityNew Orleans
Period5/04/208/04/20

Fingerprint

flow field
heat transfer
baseflow
heating
fluid
laminar flow
unsteady flow
chemical reaction
bioreactor
pumping
decomposition
mineral
prediction
chemical

Keywords

  • scalar transport
  • chaotic advection
  • thermal control

Cite this

Lensvelt, R., Speetjens, M., & Nijmeijer, H. (Accepted/In press). Heat-transfer enhancement by adaptive reorientation of flow fields. In Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA
Lensvelt, Ruud ; Speetjens, Michel ; Nijmeijer, Henk. / Heat-transfer enhancement by adaptive reorientation of flow fields. Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA. 2020.
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abstract = "Scope is enhancement of scalar transport (heat, chemical species) in engineered flow systems by reorientations of a laminar base flow. Practical applications include mixing in inline heat exchangers by downstream reorientation of baffles, stirring in bio-reactors by cyclic repositioning of impellers, and subsurface chemicals distribution for in situ minerals mining by unsteady pumping schemes. Conventional reorientation schemes consist of a periodic reorientation (in space or time) of the flow designed to accomplish efficient fluid mixing. However, whether this approach indeed yields optimal scalar transport for significant diffusion and/or chemical reactions is unclear. The present study explores an alternative approach: adaptive reorientation of the flow by interval-wise selection of the reorientation that is predicted to yield optimal scalar transport for a future time horizon. Key enabler for fast predictions is a compact model based on the spectral decomposition of the scalar evolution in the baseflow. The adaptive reorientation scheme is investigated for a representative problem: enhanced heating of a cold fluid in a 2D circular domain by an unsteady flow driven by step-wise activation of moving boundary segments. This reveals that the adaptive reorientation scheme can substantially acceleratethe heating compared to conventional time-periodic reorientation designed for efficient mixing and thus demonstrates its potential for attaining optimal scalar transport in reoriented flows.",
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Lensvelt, R, Speetjens, M & Nijmeijer, H 2020, Heat-transfer enhancement by adaptive reorientation of flow fields. in Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA. 5th Thermal and Fluids Engineering Conference (TFEC), New Orleans, United States, 5/04/20.

Heat-transfer enhancement by adaptive reorientation of flow fields. / Lensvelt, Ruud; Speetjens, Michel; Nijmeijer, Henk.

Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA. 2020.

Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review

TY - GEN

T1 - Heat-transfer enhancement by adaptive reorientation of flow fields

AU - Lensvelt,Ruud

AU - Speetjens,Michel

AU - Nijmeijer,Henk

PY - 2020

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N2 - Scope is enhancement of scalar transport (heat, chemical species) in engineered flow systems by reorientations of a laminar base flow. Practical applications include mixing in inline heat exchangers by downstream reorientation of baffles, stirring in bio-reactors by cyclic repositioning of impellers, and subsurface chemicals distribution for in situ minerals mining by unsteady pumping schemes. Conventional reorientation schemes consist of a periodic reorientation (in space or time) of the flow designed to accomplish efficient fluid mixing. However, whether this approach indeed yields optimal scalar transport for significant diffusion and/or chemical reactions is unclear. The present study explores an alternative approach: adaptive reorientation of the flow by interval-wise selection of the reorientation that is predicted to yield optimal scalar transport for a future time horizon. Key enabler for fast predictions is a compact model based on the spectral decomposition of the scalar evolution in the baseflow. The adaptive reorientation scheme is investigated for a representative problem: enhanced heating of a cold fluid in a 2D circular domain by an unsteady flow driven by step-wise activation of moving boundary segments. This reveals that the adaptive reorientation scheme can substantially acceleratethe heating compared to conventional time-periodic reorientation designed for efficient mixing and thus demonstrates its potential for attaining optimal scalar transport in reoriented flows.

AB - Scope is enhancement of scalar transport (heat, chemical species) in engineered flow systems by reorientations of a laminar base flow. Practical applications include mixing in inline heat exchangers by downstream reorientation of baffles, stirring in bio-reactors by cyclic repositioning of impellers, and subsurface chemicals distribution for in situ minerals mining by unsteady pumping schemes. Conventional reorientation schemes consist of a periodic reorientation (in space or time) of the flow designed to accomplish efficient fluid mixing. However, whether this approach indeed yields optimal scalar transport for significant diffusion and/or chemical reactions is unclear. The present study explores an alternative approach: adaptive reorientation of the flow by interval-wise selection of the reorientation that is predicted to yield optimal scalar transport for a future time horizon. Key enabler for fast predictions is a compact model based on the spectral decomposition of the scalar evolution in the baseflow. The adaptive reorientation scheme is investigated for a representative problem: enhanced heating of a cold fluid in a 2D circular domain by an unsteady flow driven by step-wise activation of moving boundary segments. This reveals that the adaptive reorientation scheme can substantially acceleratethe heating compared to conventional time-periodic reorientation designed for efficient mixing and thus demonstrates its potential for attaining optimal scalar transport in reoriented flows.

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M3 - Conference contribution

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Lensvelt R, Speetjens M, Nijmeijer H. Heat-transfer enhancement by adaptive reorientation of flow fields. In Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA. 2020.