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Published on: April 30, 2018
Pr<1 intrusion flow induced by a vertical heated wall
Feng Xu1, John C Patterson, Chengwang Lei
1School of Civil Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
This study investigates low Prandtl number (Pr<1) intrusion flows driven by heated walls in open cavities. Four flow regimes were identified, with scaling laws proposed and verified by simulations.
Area of Science:
- Fluid dynamics
- Heat transfer
- Thermodynamics
Background:
- Horizontal flow induced by vertical heated walls with low Prandtl numbers (Pr<1) is prevalent in natural and industrial settings.
- Such flows are crucial in applications involving air and liquid metals.
Purpose of the Study:
- To investigate low Prandtl number (Pr<1) intrusion flow induced by a vertical heated boundary in an open-sided cavity.
- To identify flow regimes and develop scaling relations for these flows.
Main Methods:
- Scaling analysis to reveal flow regimes based on Rayleigh and Prandtl numbers.
- Direct numerical simulations to verify the scaling analysis results.
Main Results:
- Identification of four distinct flow regimes for the intrusion flow.
- Development of scaling relations to quantify flow behavior across different regimes.
- Demonstration of different dynamical and thermal processes, including conduction-viscous, conduction-inertial, and convection-inertial dominance.
Conclusions:
- The scaling analysis accurately predicts the behavior of low Prandtl number intrusion flows.
- Numerical simulations confirm the validity of the proposed scaling relations.
- The findings provide a quantitative framework for understanding and predicting these flows in various applications.
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