This paper describes a proton exchange membrane (PEM) fuel cell system model for automotive applications that includes an air compressor, cooling system, and other auxiliaries. The fuel cell system model has been integrated into a vehicle performance simulator that determines fuel economy and allows consideration of control strategies. Significant fuel cell system efficiency improvements may be possible through control of the air compressor and other auxiliaries. Fuel cell system efficiency results are presented for two limiting air compressor cases: ideal control and no control. Extension of the present analysis to hybrid configurations consisting of a fuel cell system and battery is currently under study.

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This paper incorporates a methanol reformer model with a proton exchange membrane (PEM) fuel cell system model for automotive applications. The reformer model and fuel cell system model have been integrated into a vehicle performance simulator that determines fuel economy and other performance features. Fuel cell vehicle fuel economy using on-board methanol reforming is compared with fuel economy using direct-hydrogen fueling. The overall performance using reforming is significantly less than in a direct-hydrogen fuel cell vehicle.

As a result of recent curriculum revisions, the mechanical engineering faculty at the United States Military Academy teaches the formal design process “just in time” for students to apply the process to their capstone design projects. The design process consists of several phases and incorporates many engineering tools. During the initial offering of the course, Mechanical Engineering Design, instructors assigned students to capstone design teams early in the course. As the instructor taught the design process, team members applied the concepts to their capstone project. Based on instructors’ and students’ feedback, faculty revised the course structure to teach the design process in the context of a simple, in-class design project (design a portable illumination device) during the first half-semester. All in-class exercises were collaborative, hands-on experiences based on the project. To reinforce topics introduced in class and ensure all students develop a firm foundation in the design process, a separate common customer need (a device to store a West Point class ring) was the focus of all individual homework. Each student developed a design, built a prototype, and wrote an individual design report. Subsequent to formal design process instruction, students formed capstone teams and began their one and one-half semester capstone design projects. Results indicate that students more thoroughly understood the design process and its associated engineering tools allowing capstone teams to progress more efficiently through conceptual design; order parts, build prototypes, and test prototypes much earlier than the previous year; and enjoy a successful capstone experience.

The mechanical engineering faculty at the United States Military Academy recently implemented an integrated, two-course thermal-fluid systems sequence that presents fundamental thermodynamics and fluid mechanics topics. Instructors introduce students to these topics by exploring operational aspects of five complex systems: a helicopter, a power plant, a total air-conditioning system, an automotive system, and a high performance aircraft. Additionally, both courses incorporate laboratories, demonstrations and hands-on educational aids, design projects, and self-learning opportunities to reinforce understanding of fundamental concepts. Results from the first year the sequence was taught indicate students prefer learning topics from a global perspective and integrating thermodynamics and fluid mechanics topics reinforces student learning and retention of fundamental concepts. Challenges to teaching an integrated thermal-fluid systems sequence include lack of availability of textbooks that present thermodynamics and fluid mechanics topics in a truly integrated manner and establishing equivalency of courses within the integrated sequence with courses taught at other universities for those students on semester exchange programs.