Characterization of the response of microfluidic fuel cells to complex 3D fluid dynamics patterns

• Applicant: Professor Dr. Christian Joachim Kähler
• Subject Area: Fluid Mechanics
• Term: from 2013 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 220176835

Microfluidic fuel cells (MFCs) are a recent class of membraneless, miniaturized fuel cells in which the two streams of fuel and oxidant flow in parallel in a microchannel without turbulent mixing. Due to their high future potential in several key branches of industry (cell phones, PDAs, clinical diagnostic tests), the optimization and improvement of their performance is currently an important task. One possibility to enhance the energy density and fuel utilization of MFCs in an effective and inexpensive way is the use of 3D flows, in which velocity components perpendicular to the main flow direction are present. Although this concept has been successfully applied in simple configurations, a conclusive analysis that could reveal the full potential of this approach and show the optimized configurations is currently unavailable. The proposed project intends to make use of advanced volumetric microscopic velocimetry methods to systematically examine the response of MFCs to the 3D flow patterns. The analysis will be carried out on innovative MFC architectures with curved geometries, able to cover a wide range of 3D flow patterns. The proposed project intends to answer the following fundamental questions related to this approach: (i) how do the power and fuel utilization of MFCs scale with the magnitude of secondary flows? (ii) What is the role played by the shape and position the fuel/oxidant interface? (iii) Can complex 3D patterns be used to consistently increase the performance of MFCs?

• DFG Programme: Research Grants