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Dispersion phenomena in helical flow in a concentric annulus.
Young Seok Song1, Howard Brenner
1Polymer System Division/Fiber System Engineering, Dankook University, Suji-gu, Yongin-si, Gyenggi-do, 448-701, Republic of Korea. youngseoks@gmail.com
The Journal of Chemical Physics
|December 17, 2009
Summary
This study models solute dispersion in helical flow, revealing robust macrotransport processes for complex phenomena. Findings support helical flow applications in exchangers, drilling, and advanced fractionations.
Area of Science:
- Fluid dynamics
- Transport phenomena
- Chemical engineering
Background:
- Helical flow, a combination of Poiseuille and Couette flows, is crucial in various industrial applications.
- Understanding solute dispersion in helical flow is essential for optimizing processes like heat exchange and separations.
- Taylor dispersion, a key phenomenon, describes solute spreading in fluid flow.
Purpose of the Study:
- To develop an analytic model for multidimensional Taylor dispersion in helical flow within a concentric annulus.
- To investigate the influence of thermophoresis (thermal diffusion) on solute dispersion under helical flow conditions.
- To analyze macroscopic transport parameters using microscopic physicochemical properties.
Main Methods:
- A multiscale approach was employed to examine dispersion phenomena.
- An analytic model was developed to address multidimensional Taylor dispersion.
- Numerical simulations were conducted to validate the mathematical model's results.
Main Results:
- The study presents a validated analytic model for Taylor dispersion in helical flow.
- Macroscopic parameters like average solute velocity and dispersivity were successfully analyzed.
- Macrotransport processes were found to be robust and capable of handling multidimensional dispersion.
Conclusions:
- The developed model provides a theoretical framework for understanding and predicting solute dispersion in helical flow.
- The findings confirm the robustness of macrotransport processes in complex flow systems.
- This research offers a foundation for optimizing helical flow applications in tube exchangers, oil drilling, and field flow fractionations.
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