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Published on: September 11, 2020
A New Void Fraction Measurement Method for Gas-Liquid Two-Phase Flow in Small Channels
Huajun Li1, Haifeng Ji2, Zhiyao Huang3
1State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China. lihuajun@zju.edu.cn.
A new method uses a laser diode and machine learning to accurately measure gas-liquid void fraction in small channels, overcoming flow pattern influences. This low-cost system offers a reliable alternative for two-phase flow analysis.
Area of Science:
- Fluid Dynamics
- Measurement Science
- Machine Learning Applications
Background:
- Accurate void fraction measurement is crucial for understanding gas-liquid two-phase flow dynamics.
- Conventional methods often struggle with flow pattern variations and high costs.
- Small channel flows present unique challenges for measurement techniques.
Purpose of the Study:
- To develop a novel, cost-effective void fraction measurement method for gas-liquid two-phase flow in small channels.
- To overcome the limitations of existing techniques, particularly their sensitivity to flow patterns.
- To validate the proposed method's effectiveness and accuracy across various flow regimes.
Main Methods:
- Utilized a laser diode and a 12x6 photodiode array sensor.
- Employed machine learning techniques, including Fisher Discriminant Analysis (FDA) for flow pattern identification.
- Applied Support Vector Machine (SVM) for void fraction modeling based on identified flow patterns.
Main Results:
- Successfully developed and validated a void fraction measurement system for small channels.
- The proposed method accurately measured void fraction across bubble, slug, stratified, and annular flow patterns.
- Achieved satisfactory measurement accuracy, demonstrating the system's effectiveness.
Conclusions:
- The developed low-cost laser diode system offers a viable and accurate solution for void fraction measurement in gas-liquid two-phase flow.
- The machine learning-based approach effectively mitigates the impact of flow pattern variations.
- This research provides a cost-effective and robust alternative to conventional measurement systems.
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