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The flow patterning capability of localized natural convection
1Department of Chemical Engineering, National Taiwan University, Taipei, 10617 Taiwan. lingchao@ntu.edu.tw.
Physical Chemistry Chemical Physics : PCCP
|October 7, 2016
Summary
This study introduces a natural convection method to control material alignment using heat sources. A dimensionless model identifies key parameters (Grashof and Prandtl numbers) for predictable flow patterning in optics, electronics, and biosciences.
Area of Science:
- Fluid dynamics
- Heat transfer
- Material science
Background:
- Controlling material alignment via fluid flow is crucial for applications in optics, electronics, and biosciences.
- Natural convection, driven by temperature gradients, offers a potential mechanism for fluid flow control.
Purpose of the Study:
- To develop a natural-convection-based method for creating controlled spatial flow patterns.
- To analyze the patterning resolution capability using a mathematical model and experimental validation.
Main Methods:
- Utilized natural convection induced by spatially controlled heat sources.
- Developed a nondimensionalized mathematical model correlating flow patterning resolution with Grashof (Gr) and Prandtl (Pr) numbers.
- Employed an angularly configured heating wire for efficient numerical and experimental analysis.
Main Results:
- Identified two key dimensionless parameters (Gr and Pr) governing flow pattern and resolution.
- Proposed a flow pattern state diagram to guide the selection of operating conditions.
- Achieved consistent resolution results between model predictions and experimental data.
Conclusions:
- The developed method effectively controls spatial flow patterns for material alignment.
- The identified dimensionless parameters and state diagram provide a framework for optimizing flow patterning.
- This approach offers a reliable method for applications in optics, electronics, and biosciences.
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