0
Research Papers

Study of Water Droplet Removal on Etched-Metal Surfaces for Proton Exchange Membrane Fuel Cell Flow Channel

[+] Author and Article Information
S. Shimpalee

Department of Chemical Engineering,
University of South Carolina,
Columbia, SC 29208
e-mail: shimpale@cec.sc.edu

V. Lilavivat

National Metal and Materials Technology Center,
National Science and Technology Development Agency,
114 Thailand Science Park,
Pathum Thani 12120, Thailand

1Corresponding author.

Manuscript received November 4, 2015; final manuscript received March 7, 2016; published online April 5, 2016. Assoc. Editor: Matthew Mench.

J. Electrochem. En. Conv. Stor. 13(1), 011003 (Apr 05, 2016) (7 pages) Paper No: JEECS-15-1004; doi: 10.1115/1.4033098 History: Received November 04, 2015; Revised March 07, 2016

Within a proton exchange membrane fuel cell (PEMFC), the transport route of liquid water begins at the cathode catalyst layer, and then progresses into the gas diffusion layer (GDL) where it then goes into the flow channel. At times, significant accumulation of liquid droplets can be seen on either side of the membrane on the surface of the flow channel. In this work, liquid water and the flow dynamics within the transport channel were examined experimentally, with the channel acting as an optical window. Ex situ interpretations of the liquid water and flow patterns inside the channel were established. Liquid water droplet movements were analyzed by considering the change of the contact angle with different flow rates. Also, various surface roughness of stainless steel was used to determine the relationships between flow rate and the contact angles. When liquid water is found within the gas channels of PEMFCs, the channels' characteristic changes become more dominant and it becomes more of a necessity to monitor the effects. Physical motion of water droplets in the flow channels of PEMFCs is important. The surface roughness properties were used to describe the contact angle and the droplet removal force on the stainless steel flow channel.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Schematic of contact angle of droplet wetted to surface

Grahic Jump Location
Fig. 2

Photograph of the flow channel used in this study (channel width = 4 mm, channel depth = 2 mm, and channel length = 120 mm)

Grahic Jump Location
Fig. 3

AFM images of cross sections and 3D of the sample's surfaces

Grahic Jump Location
Fig. 4

Schematic of the drop in the flow channel used in this study

Grahic Jump Location
Fig. 5

(a) Image of the droplet in the presence of air flow and (b) schematic view of control volume chosen for analysis

Grahic Jump Location
Fig. 6

Static contact angle and height of 10 μl water droplet on stainless steel plate

Grahic Jump Location
Fig. 7

Schematic illustration of the surface model with a series of uniform needles

Grahic Jump Location
Fig. 8

Dynamic images of the water droplet on electrochemically etched stainless steel plate (Ra = 0.73 μm) at different Re

Grahic Jump Location
Fig. 9

Water droplet profile at different Reynolds numbers: (a) Ra = 0.02 μm, (b) Ra = 0.27 μm, (c) Ra = 0.30 μm, (d) Ra = 0.41 μm, and (e) Ra = 0.73 μm. _____: RE = 0; ........: RE = 185, _ _ _ _ _ : RE = 370; _ . _.: RE = 555; __ __: RE= 740; __ . __: RE = 925.

Grahic Jump Location
Fig. 10

The plot of pressure drop at critical point versus surface roughness (Ra)

Grahic Jump Location
Fig. 11

Total drag force versus Reynolds number for different roughness surface

Grahic Jump Location
Fig. 12

Relationship between the roughness factor times solid area fraction rf and the total drag force

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In