Nickel anodes, for molten carbonate fuel cell (MCFC), of various porosities were fabricated using tape casting and firing processes. The same slurry composition but different sintering temperatures, 700 and 900°C, were used to obtain different anode porosities. Combined experimental and computational techniques were used to study the influence of anode porosity on the performance of molten carbonate fuels cell. The power generated by the 20.25 cm2 class MCFC single cell was experimentally measured at 650°C in humidified hydrogen with respect to the porosity of the anodes. The computational aspect involved the modeling of the microstructure of the sintered porous anodes which included measured size distribution of Ni powder used and porosities of the manufactured materials. For the best performing single cell, the optimal porosity for the nickel MCFC anode was experimentally determined to be 55%. Computations revealed that the specific surface area, which is a determining factor in electrochemical reactions, reaches a maximum at a porosity of 52%.
In the present paper we present the approach for modeling of the elastic behavior of open-cell metallic foams concerning non-uniform pore size distribution. This approach combines design of foam structures and numerical simulations of compression tests using finite element method (FEM). In the design stage, Laguerre-Voronoi tessellations (LVT) were performed on several sets of packed spheres with defined variation of radii, bringing about a set of foam structures with porosity ranging from 74 to 98% and different pore size variation quantified by the coefficient of pore volume variation, CV(V), from 0.5 to 2.1. Each structure was numerically subjected to uni-axial compression test along three directions within the elastic region. Basing on the numerical response, the effective Young’s modulus, Eeff, was calculated for each structure. It is shown that the Eeff is not only dependent on the porosity but also on the pore size variation.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.