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Fuel cell vehicles powered using Hydrogen/air fuel cells have received a lot of attention recently as possible alternatives to internal combustion engine. However, the combined problems of on-board Hydrogen storage and the lack of Hydrogen infrastructure represent major impediments to their wide scale adoption as replacements for IC engine vehicles. On board fuel processors that generate hydrogen from on-board liquid methanol (and other hydrocarbons) have been proposed as possible alternative sources of Hydrogen needed by the fuel cell. This paper focuses on a methanol fuel processor using steam reformation of methanol to generate the Hydrogen required for the fuel cell stack. Since the steam reformation is an endothermic process the thermal energy required is supplied by a catalytic burner.

This paper focuses on the impact of proper thermal integration between two major components of the indirect methanol fuel cell vehicle fuel processor (reformer and burner). The fuel processor uses the steam reformation of methanol to produce the hydrogen required by the fuel cell. Since the steam reformation is an endothermic process, the required thermal energy is supplied by a catalytic burner. The performance of the fuel processor is very strongly influenced by the extent of thermal integration between the reformer and burner. Both components are modeled as a set of CSTRs (Continuous Stirred Tank Reactors) using Matlab/Simulink. The current model assumes no time lag between the methanol sent into the reformer and the methanol sent into the burner to generate the necessary heat for the reformer reactions to occur.

This paper deals with system level analysis of a methanol fuel processor for an indirect hydrogen-Air based Fuel Cell Vehicle (FCV) based on a Proton Exchange Membrane (PEM) fuel cell stack. This analysis focuses on the performance of the fuel processor from the viewpoint of efficiency and the requirements placed on it by the Fuel Cell Vehicle. It is widely accepted that hydrogen supply is an important issue in PEM-FC vehicle systems. The lack of a well-entrenched hydrogen infrastructure and the nascent state of hydrogen storage technology has led to development of on-board hydrogen generation systems to meet the fuel cell hydrogen demand. The primary fuel is typically a Hydrocarbon (methanol, gasoline) which is then “reformed” in a fuel processor to generate the hydrogen needed by the fuel cell stack. A great deal of effort has been expended in developing fuel processors that would satisfy the rigorous demands of automotive applications.

A principal motivation for introducing alternative fuels is to reduce air pollution and greenhouse gas emissions. A comprehensive evaluation of the reductions must include all Life Cycle activities from the vehicle operation to the feedstock extraction. This paper focuses on the fuel upstream activities only. We compare the results and methods of the three most comprehensive existing fuel upstream models in the U.S.A. and we explore the differences and uncertainties of these types of analyses. To explicitly include the impact of uncertainties, we create a new model using the following approaches: Instead of using a single value as input, the new model deals with ranges around the most probable value. Ranges are discussed and calibrated by an expert network, in terms of their relative probability. Probabilistic function techniques are applied to study the impact of the uncertainties on the model output.

This paper addresses the critical need to incorporate realistic models of the air supply sub-system in fuel cell system performance analysis. The paper first presents the dominant performance issues involved with the air supply operation in the fuel cell system. The report then goes on to propose a methodology for an air supply model that addresses many of the performance issues. Most importantly, a model is needed with a defined set of performance criteria and data input format, one that can accommodate multiple air supply configurations, and one that realistically and accurately simulates the air supply operation and its effect on the system power and efficiency. The paper concludes that it is possible to compare alternative air supply components under the constraint of maximizing the instantaneous net fuel cell system efficiency for a dynamic vehicle driving cycle under various ambient conditions.