Abstract
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.
| Original language | English |
|---|---|
| Title of host publication | Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA |
| Publication status | Accepted/In press - 2020 |
| Event | 5th Thermal and Fluids Engineering Conference (TFEC) - New Orleans, United States Duration: 5 Apr 2020 → 8 Apr 2020 |
Conference
| Conference | 5th Thermal and Fluids Engineering Conference (TFEC) |
|---|---|
| Country | United States |
| City | New Orleans |
| Period | 5/04/20 → 8/04/20 |
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Keywords
- scalar transport
- chaotic advection
- thermal control
Cite this
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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 proceeding › Conference contribution › Academic › peer-review
TY - GEN
T1 - Heat-transfer enhancement by adaptive reorientation of flow fields
AU - Lensvelt, Ruud
AU - Speetjens, Michel
AU - Nijmeijer, Henk
PY - 2020
Y1 - 2020
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.
KW - scalar transport
KW - chaotic advection
KW - thermal control
M3 - Conference contribution
BT - Proceedings 5th Thermal and Fluids Engineering Conference (TFEC), April 5–8, 2020, New Orleans, LA, USA
ER -