Experimental Study of Flow Boiling Regimes Occurring in a Microfluidic T-Junction

Area of Science:

• Heat Transfer
• Fluid Dynamics
• Microfluidics

Background:

• Microchannel flow boiling is crucial for cooling high-heat-flux electronics.
• Understanding two-phase flow patterns in microchannels is essential for optimizing cooling performance.
• T-shaped microchannels present unique challenges for flow boiling dynamics.

Purpose of the Study:

• To investigate the evolution characteristics of two-phase flow patterns in T-shaped microchannels.
• To analyze the influence of flow rate and channel size on microchannel flow boiling regimes.
• To provide a quantitative description of flow patterns under varying conditions.

Main Methods:

• Preparation of T-shaped microchannels with varying dimensions.
• Design and implementation of an experimental platform for flow boiling visualization.
• Experimental observation and quantitative description of flow patterns.

Main Results:

• Vaporization core migration from branch to main channels with increasing wall temperature.
• Identification of flow regimes: extrusion fracture, bubble, plug-annular alternating, and annular flow.
• Annular flow further classified into intermittent and stable annular flow.
• High flow rate and small channel size suppress bubble flow and promote annular flow.

Conclusions:

• Flow patterns in T-shaped microchannels are sensitive to temperature, flow rate, and channel size.
• Optimizing flow rate and channel dimensions can enhance the efficiency of microchannel flow boiling.
• The findings contribute to the design of advanced cooling systems for electronic devices.