A Unique Approach to Teaching Thermodynamics

CPT Blace C. Albert – Instructor, Dr. Ozer Arnas – Visiting Professor, Dr. Margaret Bailey – Assistant Professor, MAJ Shawn Klawunder – Instructor, COL John S. Klegka – Mechanical Engineering Division Director, MAJ David Wolons – Assistant Professor

Department of Civil and Mechanical Engineering

United States Military Academy

West Point, NY 10996 USA

Abstract

The Department of Civil and Mechanical Engineering at the United States Military Academy (USMA) offers a course in thermodynamics that is well known among the Corps of Cadets due to its uniqueness and applicability. Cadets from every department in the academy enroll in the course and are taught by a faculty that is composed of both military and civilian professors. The classroom and laboratory experiences that have been designed over the past decade provide students with a broad introductory exposure to thermodynamics while focusing on very relevant applications. This paper presents an overview of the thermodynamic experience created at the USMA and offers several examples of its uniqueness.

Introduction

The United States Military Academy (USMA) located in West Point, New York includes thirteen different academic departments offering over sixty academic majors. While pursuing a four-year college degree, the students that attend the academy are also training to serve as officers in the United States Army and are therefore known as cadets. The complete student body is referred to as the Corps of Cadets and includes representation from every state in the nation as well as numerous foreign countries. The mission of the USMA (USMA Office of the Dean, 1998) is “to educate, train, and inspire the Corps of Cadets so that each graduate is a commissioned leader of character committed to the values of Duty, Honor, Country; professional growth throughout a career as an officer in the United States Army; and a lifetime of selfless service to the nation.”

West Point’s Department of Civil and Mechanical Engineering offers an ABET accredited degree in mechanical engineering (ME). Cadets enrolled in ME must successfully complete a course of study very similar to that required by their peers at civilian institutions. Each year, approximately 75 cadets select mechanical engineering as a major and they typically enroll in Thermodynamics in their first semester of their third year. However, regardless of academic major, all students supplement their general education or core requirements at the USMA with a five-course engineering sequence capped with at least one design course. Therefore, thermodynamic instructors are challenged to teach this course to students majoring in a variety of areas such as language, history, political science, as well as mechanical engineering.

The laws of thermodynamics are the same regardless of whether they are taught to an engineering major or a history major. Therefore, thermodynamics is not offered as two separate courses, one for engineering majors and the other for humanities oriented majors. Instead all students take the same course and there is a mixture of majors in any given class. One crucial advantage in this method success is that all cadets must take the same core curriculum, including basic science courses (mathematics, physics, and chemistry). This foundation gives our students a common background from which to build regardless of academic major. The total annual enrollment in Thermodynamics typically reaches 500 or roughly half of all eligible cadets. Large course enrollment coupled with the academy’s restriction of a maximum of 18 cadets per section, results in the creation of thirteen to fifteen thermodynamic sections per semester.

The course structure includes a lecture and laboratory component. There are 35 lectures, each 55 minutes in length that follow a classical textbook. The topics covered include definitions, pure substances, ideal equation of state, conservation of mass and energy, and the second law. In order to enhance the student’s learning, several applications are studied in detail including steam power plants, air standard cycles, emissions, vapor compression refrigeration systems, psychrometrics, and air conditioning. The lectures are further augmented by an ABET design project and four laboratories focused on steam turbines, SI/CI engine comparison, Cooperative Fuel Research (CFR) engines, and gas turbines. We complete our course with a visit to the academy power plant. Each of these areas will be discussed in more detail in later sections of this paper. The course also includes two 30-minute quizzes and two 55-minute tests. The final cumulative examination completes the cadet’s course requirements.

Thermodynamics at the USMA is designated as either EM301 or EM301A. Most cadets pursuing an ABET accredited engineering degree, such as mechanical or civil engineering, enroll in the EM301A version of the course. These engineering cadets attend the same lectures and laboratories as the students enrolled in EM301; however, the engineers also complete a group design project, as defined by ABET. The course credit for EM301 is three, with an additional half credit for those enrolling in EM301A.

Thermodynamics Faculty

The faculty team that teaches EM301 is typical in composition to other teaching teams found in large enrollment courses at USMA. The team reflects the diversity of the USMA faculty. It is a blend of senior military faculty, civilian faculty, and junior military faculty. Each of these groups brings special talents to the teaching team. At the USMA, the senior military faculty is responsible for filling most of the administrative and leadership positions. They typically have six to fifteen years of service on the faculty and help provide continuity and stability to the academy. In addition, these faculty members are involved in the development and improvement of academic programs (such as the mechanical engineering program) as well as individual courses. Each has a PhD in a relevant discipline. They make up about 15% of the overall faculty.

Civilian faculty members increase the depth of expertise on the teaching team, help provide continuity, and provide a different perspective from that of a predominantly military faculty. These faculty members serve similar roles as their colleagues at civilian colleges and universities. Each civilian faculty member also has a Ph.D. in a relevant discipline. Civilian faculty comprise between 20-25% of the overall faculty.

The largest part of the teaching team is made up of junior military faculty. These educators are active duty military officers, typically in their seventh to twelfth year of service in the United States Army. The officers are carefully selected from among the best in the service. Each is a volunteer who comes to the USMA after the completion of a Master's program in a relevant discipline at a leading civilian university. These officers are the heart of the faculty at West Point both from the standpoint of their numbers (about 60-65% of the faculty) as well as the number of cadets that each of them teaches. In addition, they serve as role models for the cadets to emulate. On a daily basis cadets interact with successful officers and see the level of dedication and professionalism that each aspires to achieve. The mix of skills, education, and experience make the faculty teaching team well equipped to present the latest material in an effective and challenging fashion to the students.

In order to prepare incoming faculty for their unique teaching experience at the USMA, each department runs a new instructor training program during the summer prior to the first semester of instruction. The Department of Civil and Mechanical Engineering calls this program the Instructor Summer Workshop (ISW). ISW lasts six weeks and is structured not only to train the instructors in the art of active learning, but also to teach them the department standards and orient them to the West Point community. The goal of ISW is to train the instructors so that they have a level of competence and confidence such that the cadets recognize them as experienced instructors.

ISW begins with an introduction and orientation from the department head. The first full week commences with a Teaching Techniques Workshop that includes several references to the engineering education research conducted by Wankat and Oreovicz (1993) as well as Lowman (1995). Table 1 summarizes the various topics covered during this initial, three-day workshop. Senior faculty, who have taught at the USMA for several years, conduct all seminars. They model all of the topics discussed in their own presentations and they also teach four different classes of varying subjects in order to demonstrate various teaching techniques.

The new instructors then enter several weeks in which they are required to teach lessons from the course they will teach in the fall. They begin by teaching a short, 30 minute long class to give them a taste of the difficulty that can be encountered in living up to the department’s expectations of a class. New instructors then present six 55-minute long classes over the next three weeks. The classes are spread out in order to give the new instructors ample time to prepare and make improvements. In every class, several senior faculty attend in order to ask typical questions that could be expected from the cadets. They also provide the new instructor with immediate oral and written feedback at the conclusion of the class. In addition to this, every class is videotaped so that the instructors can view the class for themselves, making notes of what they did well and what was awkward or distracting.

Table 1 - ISW Teaching Techniques Workshop
Seminar
/
Subject
1 / Learning to Teach in the Civil and Mechanical Engineering Department
2 / Principles of Effective Teaching and Learning
3 / Teaching Assessment
4 / An Introduction to Learning Styles
5 / Organizing a Class
6 / Planning the Class
7 / Communication and Presentation Skills
8 / Questioning Techniques
9 / Classroom Assessment Techniques
10 / Systematic Design of Instruction
11 / Teaching with Technology

During the last week of classes, the new instructors also receive peer evaluations that not only provide additional feedback, but also train the new instructors on how to provide useful assessment. The assessment process used during ISW does not end once the fall semester begins. Throughout the year a new instructor can expect to have three to five visits from senior faculty and peers. These visitors will attend a class in which they fill out a Teaching Assessment Worksheet (included as Appendix 1). The purpose of the visit is to assess the instructor on technical expertise, lesson organization, conduct of the class, and the classroom environment. These assessments are maintained in an instructor’s Teacher Portfolio. This notebook houses the assessments along with other documents that assist the instructors in conducting the on-going process of self-assessment. For a more detailed description of the ISW experience, the interested reader should refer to Hanus and Evans (2001).

Course Background

The goal of EM301 is to provide cadets with a practical and relevant engineering science background in thermodynamics. Additionally, engineering majors enrolled in EM301A complete an engineering design project and therefore gain design experience in thermodynamics. The course also provides the groundwork for subsequent studies in engineering sciences and advanced energy topics. In addition, numerous course requirements enhance both oral and written communication skills. The course is designed to provide a solid foundation in classical thermodynamics through the study of three broad topic areas including preliminary topics, methods and tools of analysis, and relevant applications. Refer to Table 2 for a complete summary of topic coverage.

Table 2 – Summary of Topics Explored in EM301
Subject
/
Lessons
Introduction to thermodynamic concepts and nomenclature / 2
Steam tables / 2
Ideal gas equation of state and energy transfer concepts / 2
1st Law of Thermodynamics / 6
2nd Law of Thermodynamics / 3
Thermodynamic devices and adiabatic efficiencies / 1
Steam vapor power cycles / 5
Internal combustion engines / 5
Automotive emissions / 1
Gas turbine engines / 4
Vapor-compression refrigeration cycles / 2
Total air conditioning applications (psychrometrics) / 2
Review classes / 3
Exams / 2

EM301 begins with a series of lessons on preliminary topics to allow the student to understand and internalize the language of thermodynamics. These first lessons include discussions on basic definitions, properties of substances, and the ideal gas law. Here, the vapor dome is presented and the cadets learn how it is used to fix states and properties. The methods and tools of analysis section of the course begins with a lesson on energy transfers in the form of heat and work. Instructors introduce the 1st and 2nd Laws of Thermodynamics. Students apply the laws to closed and open systems. Prior to the introduction of detailed applications, the students learn the methods involved in determining adiabatic efficiencies for various mechanical devices.

Once this basic foundation has been laid, students apply their newly acquired knowledge to studying various cycles as described in Table 2. They begin by learning how to analyze steam vapor power cycles using the Mollier diagram and applicable steam tables. The steam vapor power cycle configurations analyzed range in complexity from the ideal Rankine cycle to actual reheat and regenerative cycles. Cadets then complete a block of instruction on internal combustion engines to include actual and ideal spark-ignition and compression-ignition cycles. An automotive emissions lesson is included to present relevant current automotive innovations in the area of pollution control. Gas turbine engine cycles are examined next. The students first study the ideal Brayton cycle and then both ideal and actual regenerative gas turbine engines. In addition, ideal and actual jet propulsion cycles are included. The course concludes with lessons on the vapor-compression refrigeration cycle (ideal and actual) and total air conditioning applications using the psychrometric chart.