Mechanical Engineering Commons^™

Design Of A 300cm2 Pemfc Stack With Force And Cfd Simulation To Optimize Flow Channels, Gasket Design, And Clamping Forces., Robert M. Ench

Electronic Theses and Dissertations

Proton exchange membrane fuel cells are important to the future of green energy as hydrogen can be made with green technologies and store energy for later use. Fuel cells can efficiently convert the hydrogen to electricity as needed. This study uses Solidworks simulation to make design improvements to the fuel cell before the prototype build stage of testing; this saves money and time by reducing the prototype builds needed.

In this study, a multi-channel serpentine design with two outlets versus a single outlet is evaluated using CFD to investigate pressure drop. Lower pressure drops are desirable as less energy input …

Numerical Studies On Liquid Water Transport In Pemfc Cathode With Biomimetic Flow Field Designs, Duy-Khang Dang

Electronic Theses and Dissertations

The performance and durability of proton exchange membrane fuel cells (PEMFCs) are greatly influenced by their water management capability. Therefore, novel flow field designs have been developing by researchers for the improvement of PEMFCs. Among those designs, novel biomimetic designs or so-called nature-inspired designs have captured special attention from researchers due to their capability of distributing fluids effectively with their prominent characteristics such as low pressure drops and efficient fluid distribution. This thesis presents a numerical investigation of the liquid water transport in PEMFC cathode with various biomimetic flow field designs. It includes a symmetrical biomimetic flow field design based …

Measurement Of Current Distribution In The Land Channel Direction Of A Proton Exchange Membrane Fuel Cell, Chinmay Kulkarni

Dissertations, Master's Theses and Master's Reports

A fully functional proton exchange membrane fuel cell with single land channel geometry on the cathode and segmented anode current collector with 9 mm² active area with a 350μm spatial resolution was utilized to measure the local current distribution in the land channel direction. A distinguished printed circuit board approach was used for the data acquisition to adapt to any flow field design.

Performance of this segmented cell was examined at dry, wet and moderate humidity settings to study the water transport phenomenon in the PEMFC. In the dry condition at 60 ͦ C with 0% relative humidity, the …

Water Transport In Polymer Electrolyte Fuel Cells: An Exploration Of Net Water Drag In Real Time, Susan Katherine Reid

Masters Theses

Polymer electrolyte fuel cells (PEFCs) are a promising alternative energy source. One challenge preventing widespread use of this technology is water management. A balance must be reached between providing sufficient water for membrane ionic conductivity while maintaining low enough water content to mitigate the reduction of available reaction sites in the cathode catalyst layer due to liquid water build up. Much exploration of this area of fuel cell research has been conducted, but the details of water transport in an operating fuel cell are not yet fully understood. The motivation of this work was to elucidate mass transport phenomena occurring …

The Role Of Transport Phenomena In The Direct Oxidation Of Solid Fuels, Charles J. Banas

Master's Theses

Direct carbon fuel cells have shown promise for stationary power generation by utilizing the direct oxidation of a solid carbon fuel source at the anode. In laboratory settings, researchers have reported up to 300mA/cm2 of current density from these cells types which suffer from mass transport losses. This paper studies the surface properties of the solid fuel source, and describes the process of CO2 evolution through an analogy to pool boiling. In nucleate boiling (a subset of pool boiling) vapor bubbles grow from nucleation sites where gas are trapped in micro-cavities on the surface. Carbon surfaces possess these same features, …

Design, Fabricaton, And Testing Of A Compact Quasi-Isothermal Prox Reactor Using Micro Heat Exchangers, Curtis Maurice Hebert

LSU Master's Theses

A two stage PROX reactor with micro heat exchangers was designed, built, and tested to demonstrate the ability to control the temperature in the reactor and improve PROX performance in terms of CO conversion and selectivity. The gas stream was composed of 40% H₂, 1% CO, 9% CO₂, 0.5% O₂, and 49.5% Ar. Metal foams were used to support a 5 wt% Pt/0.5 wt% Fe/γ-Al₂O₃ catalyst. Two sections of foam catalyst were used with heat exchangers positioned before and after each section. The resulting axial temperature profile of the gas stream …