The effects of chaotic advection on heat transfer

doi:10.1016/S0017-9310(96)00361-4

International Journal of Heat and Mass Transfer

Volume 40, Issue 13, September 1997, Pages 3089-3104

https://doi.org/10.1016/S0017-9310(96)00361-4 Get rights and content

Abstract

The objective of this study is to characterize a new heating process in fluids, chaotic advection. The main mechanism generating this flow is the production of spatially chaotic trajectories in an alternating Dean flow. The present work examines the effects of chaotic advection on heat transfer at low Reynolds numbers. In order to assess the enhancement of heat transfer by chaotic advection, a helical heat exchanger and a chaotic heat exchanger (both of shell-and-tube type) of the same heat-transfer surface area and the same tube length were tested. The coils were assembled from 90° bends, and the chaotic coil was produced merely by turning each bend at a ± 90° angle with respect to the previous one. Experiments were performed for Reynolds numbers ranging from 60 to 200. Temperature profiles measured in the cross-section of the coils show that chaotic advection substantially homogenizes and enhances heating. Moreover, it is shown that the homogeneity of heating in chaotic flow is almost independent of the Reynolds number. Parallel to the temperature profiles measurements, axial velocity profiles were measured by laser Doppler velocimetry at the exit from the coils and used to characterize the flow in the isothermal regime and compare the temperature profiles to the velocity profiles. Global heat-transfer measurements show that the chaotic heat exchanger is more efficient than the helical one, with an efficiency enhancement between 13 and 27%.

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Citation Excerpt :
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The effects of chaotic advection on heat transfer

Abstract

International Journal of Heat and Mass Transfer

International Journal of Heat and Mass Transfer

Chemical Engineering Science

Chemical Engineering Science

Experimental Thermal and Fluid Science

International Journal of Heat and Mass Transfer

Convective heat transfer in curved ducts

Study on forced convective heat transfer in curved pipes (1st report, laminar region)

International Journal of Heat and Mass Transfer

Effect of secondary fluid motion on laminar heat transfer in helically coiled tubes

AIChE Journal

Prediction of laminar flow and heat transfer in helically coiled pipes

Journal of Fluid Mechanics

Heat transfer for the flow of a power law fluid in a curved pipe

Journal of Indian Institute of Science

Chaotic advection by laminar flow in twisted pipe

Journal of Fluid Mechanics

Heat exchanger design based on chaotic advection

Experimental and Thermal and Fluid Science

Stirring by chaotic advection

Journal of Fluid Mechanics

Lagrangian turbulence and spatial complexity in a stokes flow

Physical Fluids

Chaotic advection in a pulsed source-sink system

Physics Fluids

Heat transfer enhancement due to slender recirculation and chaotic transport between counter-rotating eccentric cylinders

Journal of Fluid Mechanics