Investigation of two-phase transport phenomena in microchannels using a microfabricated experimental structure

Wang, Fu Min; Steinbrenner, Julie E.; Hidrovo, Carlos; Kramer, Theresa A.; Lee, Eon Soo; Vigneron, Sébastien; Cheng, Chor Hing; Eaton, John K.; Goodson, Kenneth E.

doi:10.1016/j.applthermaleng.2006.07.014

Cited by 5 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Resistance temperature detectors (RTDs) are based on the natural change in the sensor's resistance with temperature. The temperature coefficient of resistance (TCR) symbolizes the resistance change factor per degree of temperature change [23].…”

Section: Microchannel Design and Fabricationmentioning

confidence: 99%

Two-Phase Microfluidics for Semiconductor Circuits and Fuel Cells (Keynote)

Hidrovo

Kramer

Wang

et al. 2005

ASME 3rd International Conference on Microchannels and Minichannels, Parts a and B

Self Cite

View full text Add to dashboard Cite

Industrial trends are presenting major challenges and opportunities for research on two-phase flows in microchannels. Semiconductor companies are developing 3D circuits for which multilevel microfluidic cooling is important. Gas delivery microchannels are promising for PEM fuel cells in portable electronics. However, data and modeling are needed for flow regime stability, liquid entrainment/clogging, and bubble inception/departure in complex 2D and 3D geometries. This paper provides an overview of the Stanford two-phase microfluidics program, with a focus on recent experimental and theoretical progress. Microfabrication technologies are used to distribute heaters, thermometers, pressure sensors, and liquid injection ports along the flow path. Liquid PIV quantifies forces on bubbles, and fluorescence imaging detects flow shapes and liquid volume fraction. Separated flow models account for conjugate conduction, liquid injection, evaporation, and a variety of flow regimes. This work benefits strongly from interactions with semiconductor and fuel cell companies seeking validated models for product design.

show abstract

Section: Microchannel Design and Fabricationmentioning

confidence: 99%

Two-Phase Microfluidics for Semiconductor Circuits and Fuel Cells (Keynote)

Hidrovo

Kramer

Wang

et al. 2005

ASME 3rd International Conference on Microchannels and Minichannels, Parts a and B

Self Cite

View full text Add to dashboard Cite

show abstract

“…Colinart et al [171] investigated water transport within PEMFC by systematic measurements of the water transport coefficient and found that the hydrogen flow rate, the amount of vapor injected at cathode inlet, and the temperature are the main parameters influencing the water transport coefficient. Wang et al [172] investigated water formation and transport using a microfabricated experimental structure with distributed water injection as well as with heating and temperature sensing capabilities.…”

Section: Water Transport and Distributionmentioning

confidence: 99%

A Review of Water Management in Polymer Electrolyte Membrane Fuel Cells

2009

View full text Add to dashboard Cite

At present, despite the great advances in polymer electrolyte membrane fuel cell (PEMFC) technology over the past two decades through intensive research and development activities, their large-scale commercialization is still hampered by their higher materials cost and lower reliability and durability. In this review, water management is given special consideration. Water management is of vital importance to achieve maximum performance and durability from PEMFCs. On the one hand, to maintain good proton conductivity, the relative humidity of inlet gases is typically held at a large value to ensure that the membrane remains fully hydrated. On the other hand, the pores of the catalyst layer (CL) and the gas diffusion layer (GDL) are frequently flooded by excessive liquid water, resulting in a higher mass transport resistance. Thus, a subtle equilibrium has to be maintained between membrane drying and liquid water flooding to prevent fuel cell degradation and guarantee a high performance level, which is the essential problem of water management. This paper presents a comprehensive review of the state-of-the-art studies of water management, including the experimental methods and modeling and simulation for the characterization of water management and the water management strategies. As one important aspect of water management, water flooding has been extensively studied during the last two decades. Herein, the causes, detection, effects on cell performance and mitigation strategies of water flooding are overviewed in detail. In the end of the paper the emphasis is given to: (i) the delicate equilibrium of membrane drying vs. water flooding in water management; (ii) determining which phenomenon is principally responsible for the deterioration of the PEMFC performance, the flooding of the porous electrode or the gas

show abstract