Free surface bubbly flow in an open capillary channel.
Bo Wu1, Zongyu Wu2, Yong Chen3
1College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, China.
NPJ Microgravity
|July 16, 2025
Summary
This study on bubbly flow in microgravity found that higher mass quality increases critical flow rate and surface stability. However, it slightly reduces liquid flow efficiency in open channels.
Area of Science:
- Fluid Dynamics
- Microgravity Science
Background:
- Bubbly flow in open channels presents unique challenges, especially under microgravity conditions.
- Understanding frictional pressure loss and flow behavior is crucial for space applications.
Purpose of the Study:
- To develop a one-dimensional model for microgravity free surface bubbly flow.
- To investigate the relationship between drag coefficient, mass quality, and critical flow rate.
Main Methods:
- Utilized a homogeneous flow model to calculate frictional pressure loss.
- Developed a correlation between drag coefficient and mass quality.
- Integrated the model into computational fluid dynamics (CFD) simulations.
- Validated models against experimental observations.
Main Results:
- Achieved strong concordance between theoretical models, simulations, and experimental data.
- Calculated critical flow rate with an average relative error of 4.93%.
- Observed a positive correlation between mass quality and critical flow rate.
- Found that increased mass quality stabilizes the free surface but decreases liquid phase flow efficiency.
Conclusions:
- The developed one-dimensional model accurately predicts microgravity free surface bubbly flow.
- Mass quality is a key parameter influencing critical flow rate and flow stability.
- Findings enhance the theoretical understanding of fluid dynamics in microgravity environments.
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