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A transient, multi-dimensional model has been developed to simulate proton exchange membrane (PEM) fuel cells. The model accounts simultaneously for electrochemical kinetics, current distribution, hydrodynamics and multi-component transport. A single set of conservation equations valid for flow channels, gas-diffusion electrodes, catalyst layers and the membrane region are developed and numerically solved using a finite-volume-based computational fluid dynamics (CFD) technique. The numerical mod

In this paper, we report the successful synthesis of cobalt ruthenium sulfides by a facile hydrothermal method. The structural aspects of the as-prepared cobalt ruthenium sulfides were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. All the prepared materials exhibited nanocrystal morphology. The electrochemical performance of the ternary metal sulfides was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electroc

Abstract A three-dimensional computational study based on the finite volume method is carried out for proton exchange membrane (PEM) fuel cells with a Nation 117 membrane and an interdigitated flow field on the cathode. Emphasis is placed on obtaining a fundamental understanding of fully three-dimensional flow in the air cathode and how it impacts the transport and electrochemical reaction processes. For the first time, fully three-dimensional results of the flow structure, species profiles and

This paper describes a numerical study on the effect of the mixing ratio of biodiesel on combustion and emission characteristics of homogeneous charge compression ignition engines. The KIVA code coupled with Chemkin chemistry solver was used to simulated combustion and emission formation processes. A modified reduced methyl butanoate mechanism was used after combining with a reduced n-heptane mechanism to model ignition and combustion of biodiesel. The mixing ratio of biodiesel was varied from 0