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Thermal Characterization of Rarefied Flows in Rhombic Microchannels
Pamela Vocale1, Gian Luca Morini2
1Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze 181/A, 43124 Parma, Italy.
Micromachines
|December 23, 2023
Summary
This study numerically investigated gaseous flow in microchannels with rhombic cross-sections. Rarefaction and geometry significantly impact heat transfer, measured by the Nusselt number.
Area of Science:
- Fluid Dynamics and Heat Transfer
- Microfluidics and Nanofluidics
Background:
- Microchannels with rhombic cross-sections are gaining attention due to advanced fabrication methods.
- Understanding fluid behavior in these microchannels is crucial for various applications.
Purpose of the Study:
- To numerically investigate the dynamic and thermal behavior of laminar gaseous flow in a rhombic microchannel.
- To analyze the effects of rarefaction and geometric properties on heat transfer.
Main Methods:
- Solved momentum and energy balance equations using commercial Computational Dynamics Fluid (CDF) code.
- Applied slip and H2 boundary conditions, accounting for temperature jump between wall and fluid.
- Validated numerical results against literature data for velocity profiles and Nusselt number.
Main Results:
- Rarefaction degree significantly influences the Nusselt number.
- Geometric properties, specifically the side angle of the rhombus, also have a substantial effect on the Nusselt number.
- Numerical results were validated for slip flow and continuum flow regimes.
Conclusions:
- Rarefaction and microchannel geometry are key factors governing heat transfer in rhombic cross-section microchannels.
- The study provides valuable insights for designing and optimizing microfluidic devices with rhombic geometries.
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