Session 1333

An Interdisciplinary Facilities Engineering Technology Graduate Course

William J. Hutzel, William E. DeWitt, and Timothy L. Skvarenina Purdue University, West Lafayette, IN

Abstract

A new graduate course called “Facilities Engineering Technology” is addressing the growing demand for multi-skill employees who can solve problems associated with mechanical and electrical systems in buildings. Identifying energy conservation measures and evaluating their economic impact is an important focus of the course for both mechanical and electrical systems.

Introduction

Facilities engineering is becoming an important career option for students in the Purdue School of Technology. The continuing boom in industrial and commercial construction, along with an increased emphasis on energy efficiency, has helped create a strong demand for technicians and engineers who manage mechanical and electrical equipment in modern commercial buildings. In fact, the Office of Manpower Studies within the School of Technology projects that facilities engineering will be one of the fastest growing technical careers over the next ten years.1

Figure 1 illustrates the technical skills needed by today’s facility engineer.2 Although mechanical and electrical skills are essential, the distinction between the two is becoming obscured by the increased use of instrumentation and computer controls for building management. A facilities manager with a mechanical background should understand how power quality impacts the performance of mechanical equipment. In contrast, a facilities engineer with an electrical background needs to understand how variable speed fans influence indoor air quality. The demand for multi-skill facility engineers who possess mechanical, electrical, and controls expertise will continue to increase as energy efficiency becomes a more important topic.

Mechanical Electrical

Instrument & Control Page 4.79.1 Figure 1. Today’s facilities engineer uses several technical disciplines. Course Overview

Facilities Engineering Technology is a new interdisciplinary course that begins to address the demand for multi-skill technical personnel. It is taught by one faculty member from Mechanical Engineering Technology and two faculty members from Electrical Engineering Technology. Except for having multiple instructors, the course is delivered like most technology courses on the West Lafayette campus of Purdue University. Each week, two 50-minute lectures are supported by one two-hour laboratory segment.

The course prerequisites ensure that students have a broad technical background without requiring a high level of expertise in any particular discipline. The prerequisite technical topics include introductory circuit analysis, thermodynamics, and fluid dynamics, which are an integral part of any two-course sequence in college physics. Mathematics up to and including calculus is also required. For this graduate level course a Bachelor of Science degree in engineering/ technology or equivalent industrial experience is desirable. However, undergraduate technology students with senior level standing have enrolled in the course with the approval of the instructors.

Identifying and developing interdisciplinary course materials was suprisingly easy. The textbook, Mechanical and Electrical Systems in Buildings, by Tao & Janis, was published in 1997 by Prentice Hall. As the title implies, coverage is split evenly among electrical and mechanical topics. This useful textbook touched on most of the relevant mechanical/electrical topics, without providing exhaustive detail on any one subject. Most laboratory experiments were not totally new, but evolved from similar work in related courses. The remainder of this paper documents the mechanical and electrical topics that were covered.

Mechanical Topics

The first seven weeks of Facilities Engineering Technology were devoted to the following mechanical topics. With less than two weeks available for each subject, comprehensive coverage was not possible. The goal is to introduce students to key issues from each area.

• mechanical measurements and calculations • HVAC fundamentals • piping equipment and systems • HVAC delivery systems

The mechanical measurements and calculations segment reviewed computations involving temperature, pressure, flow, and energy. Although this topic was remedial for students with a mechanical background, it was a useful starting point for students with an electrical background. Common instruments, such as manometers, barometers, flow meters, and a variety of temperature measuring devices were used to evaluate the performance of heating and cooling equipment. For example, the tons of cooling delivered by a direct expansion coil was estimated from measurements of temperature differential and air flow. Page 4.79.2 The HVAC fundamentals segment touched on a variety of issues that are important for facility engineers. The psychrometric chart illustrated how temperature and humidity impact energy use. Basic heating and cooling load calculations were also performed. Laboratory work to support this segment included using sling psychrometers for measuring the state point of indoor and outdoor air.

Figure 2 illustrates some of the equipment used during the piping equipment and systems segment. A closed loop flow network that collects energy from eight roof-mounted solar collectors has been fully instrumented for temperature, pressure, and flow measurements. Students evaluated the performance of the plate and frame heat exchanger and studied the pressure drop through the piping network. The important role of auxiliary equipment, such as air separators, expansion tanks, and pressure relief valves was also emphasized.

Figure 2. An active solar collector loop demonstrates common piping components, such as a plate & frame heat exchanger, expansion tank, flow control valve, and flowmeter.

Figure 3 highlights the equipment used during the HVAC delivery systems segment. A forced air reheat system and a dual temperature hydronic system heat or cool air inside a large environmental chamber.3,4 To help keep pace with the state of the art, both systems were recently re-designed to include modern direct digital controls (DDC). DDC is a key feature of modern “building automation” systems, which integrate all aspects of building performance into a single user-friendly user interface. Students in Facilities Engineering Technology gain an appreciation for the tremendous energy savings that can be achieved by using microprocessors to automatically modulate heating or cooling based upon the time of day or level of human

occupancy. Page 4.79.3 Figure 3. Computer controlled forced air (left) and hydronic (right) systems demonstrate mechanical equipment found in commercial buildings.

Electrical Topics

The final eight weeks of Facilities Engineering Technology were devoted to the following electrical topics. With approximately two weeks available for each subject, comprehensive coverage was not possible. The goal is to introduce students to key issues from each area.

• introduction to electricity & power quality • induction motors & variable speed drives • electrical systems and wiring • lighting

An introduction to electricity quality segment reviewed key issues regarding alternating current power and electrical safety. Although this topic was remedial for students with an electrical background, it was a useful starting point for students with a mechanical background. The Hampden consoles shown in Figure 4 were useful for demonstrating single-phase resistive and three-phase RLC loads. Each bench also had a Fluke 41 harmonic analysis meter to illustrate power quality issues that can result from nonlinear three phase loads. Page 4.79.4 Figure 4. Hampden consoles demonstrate single-phase resistive and three-phase RLC loads that are common for industrial applications. The foreground of Figure 4 shows commercial control equipment used by students to create several motor starting circuits during the segment on induction motors & variable speed drives. The equipment in Figure 5 demonstrated how significant energy savings can be achieved by using an AC variable speed drive for an induction motor. Fractional horsepower motors, digital tachometers, motor starters, and metering equipment were also used to illustrate common power applications.

Figure 5. AC variable speed drives are an important energy saving option in many commercial facilities. Page 4.79.5 The segment on electrical systems and wiring introduced large scale distribution systems. The primary components of a power system were traced from the utility to its ultimate point of use. Important concepts such as grounding, overcurrent protection, and conductor size were introduced with respect to the National Electrical Code. One laboratory exercise demonstrated how electrical system analysis software packages can be used to model electrical distribution systems.

The lighting segment highlighted the fundamentals of illumination that are applicable to building environments. A basic understanding of intensity, the visible spectrum, and color was necessary before lighting equipment and systems were introduced. Students learned how to select lighting fixtures based on output, intensity, and energy efficiency.

Impact on teaching and learning

Although the interdisciplinary Facilities Engineering Technology course required some extra coordination among the three participating faculty members, the overall experience was positive. Most of the planning meetings were held in the year leading up to the initial course offering. Once the semester was underway, the faculty members operated nearly autonomously. At the end of the semester, a wrap-up meeting coordinated a comprehensive examination and final course grades.

There were some challenges to teaching students with differing technical backgrounds. Topics that were remedial for MET students were sometimes new to EET students, and vice- versa. There was no easy remedy for this problem. Since the course is part of the graduate program, students were expected to do background work as required. With a little extra effort on the part of the instructor and student, useful technical concepts were presented to a diverse group of students.

Student feedback on the course was encouraging. All participants recognized the advantages of evaluating building systems from an interdisciplinary perspective. The disparity in technical background was not a major drawback for the students. The following student feedback was gleaned from standardized course evaluations used at Purdue University.

“I believe that this course will be helpful to me in the future because of the basic knowledge that I am acquiring”

“I would definitely recommend this course to others with M/E interests”

The greatest challenge for future offerings of Facilities Engineering Technology is boosting enrollment to acceptable levels. A total of six students, three from MET and three from EET, enrolled in the inaugural course. The ideal course size, based largely on available lab space, is between twelve and fifteen students. Getting the word out to the general student population by posting flyers and working with student counselors may solve this problem. Another strong possibility is offering this course in the evening, which would encourage participation by facility engineers from local industry. Page 4.79.6 Bibliography

1. Lisack, J.P. and Shell, Kevin D., (1993). Manpower Tid-Bit 93-5, Office of Manpower Studies, Purdue University School of Technology.

2. Williamson, Robert M., (1996) Multi-skill maintenance models for today and tomorrow, AIPE Facilities, January/February.

3. Hutzel, William J., (1998). Development of a building automation laboratory, Proceedings of the 1998 Annual Conference and Exposition, American Society for Engineering Education.

4. Hutzel, William J., (1998). Building automation for a laboratory hydronic system, Proceedings of the 1998 International Mechanical Engineering Congress and Exposition, paper # 98-WA-MET-2, American Society of Mechanical Engineers.

WILLIAM J. HUTZEL William J. Hutzel is an Assistant Professor in the MET Department at Purdue University, where his areas of expertise include HVAC and Controls. He can be reached by phone at (765) 494-7528 or by email at [email protected].

WILLIAM E. DeWITT William E. DeWitt is an Associate Professor in the EET Department at Purdue University, where his areas of expertise include electrical distribution systems and forensic engineering. He can be reached by phone at (765) 494-7906 or by email at [email protected]

TIMOTHY L. SKVARENINA Timothy L. Skvarenina is an Associate Professor in the EET Department at Purdue University, where his areas of expertise include educational methods and the modeling of electric power system devices and systems. He can be reached by phone at (765) 494-7492 or by email at [email protected]. Page 4.79.7