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Integration of concepts throughout a curriculum can aid in student understanding and retention of difficult concepts. One area that is ripe for such integration is the Thermal Sciences, where Thermodynamics, Heat Transfer, and Fluid Mechanics courses all share some common ground. In this paper, the development of experimental apparatuses, which can be used for experiments in both Thermodynamics and Heat Transfer courses, is discussed. By having undergraduate students perform laboratory experiments focused on appropriate topics for each course using the same setups, the students can relate the course materials more effectively. Four different experimental apparatuses that have been developed for use in both a basic thermodynamics course and a heat transfer course are described. In addition, the laboratory exercises developed for each course using the apparatuses are discussed. The experiments were developed using simple, practical devices. The experiments developed center around (a) a dorm-sized refrigerator, (b) a small industrial heat exchanger, (c) a cooking wok, and (d) a highintensity commercial light fixture. These are all devices that students have either encountered in everyday life, or can easily connect with. The experiments build upon this basic familiarity by applying engineering experiments to the equipment to demonstrate fundamental principles of Thermodynamics in the Basic Thermodynamics course. With this background, the students will then see the same experimental hardware in their Heat Transfer course, but will perform experiments that use the apparatus to elucidate the concepts of conduction, convection, and thermal radiation. In this way, vertical integration of pre-existing experiences, principles of thermodynamics and heat transfer concepts through the curriculum is achieved. The experiments described in this paper were developed and built by undergraduate students in the Mechanical Engineering Department at the University of Wisconsin-Milwaukee (UWM). This opportunity allowed our students to gain a greatly increased knowledge of thermodynamics, heat transfer, and experimentation. The use of students in designing and building the experiments also aided the faculty involved, as the students were able to design experiments that better addressed the needs of students in understanding course content. Introduction and Background Mechanical Engineering students at UWM, like most other schools, are required to take several courses in the thermal sciences. These required courses are Basic Engineering Thermodynamics (ME 301), Introduction to Fluid Mechanics (ME 320), and Basic Heat Transfer (ME 321.) Traditionally, the Thermodynamics and Heat Transfer courses have been almost exclusively lecture-based, while the Fluid Mechanics course has had some experimental content. Several years ago, the experimental component of the Fluid Mechanics course was transferred into a new course, Fluid Mechanics Laboratory (ME 323), so that additional time could be spent on the experimental aspects of Fluid Mechanics. The Thermodynamics and Heat Transfer courses P ge 11475.2 remained without any significant experimental component. While a primarily lecture-based instruction is sufficient for the education of some students, it has been found that many students prefer learning through a hands-on or visual approach. 1-3 The authors wanted to bring an experimental component into the Thermodynamics and Heat Transfer courses in order to shore up this potential weakness. It was noted that many students struggled with understanding the basic concepts of the courses when they are only presented in an abstract fashion through lectures without any hands-on activity to provide concrete examples of the principles being taught. By providing the students with experiments involving real-world devices, the students would be given an opportunity to connect the abstract concepts presented in lecture to devices that they either encounter everyday or equipment that is common in industry. It was desired that the students would perform the experiments in small groups, preferably groups of three. This activity should benefit all students, but in particular would help the learning of those students who learn better visually while conducting experiments. The authors also noted that many students don't connect the material from Thermodynamics and Heat Transfer very well. While the students learn about the concept of Heat Transfer in Thermodynamics, many do not seem to quickly connect the material learned in Thermodynamics to the Heat Transfer course. The authors have found that many of our students think of these courses as distinct subjects, rather than interconnected topics involving energy. To help bridge this gap, the authors decided that the experiments to be used in each course should be based off the same hardware. The students would perform one experiment focused on Thermodynamicsrelated material on one device in Thermodynamics, and then would use the same device in a future semester in the Heat Transfer course to perform a more detailed Heat Transfer experiment. In this way, vertical integration of the curriculum has been achieved, and the students would be able to relate the different courses to the same equipment to see how the two subjects are intertwined. To further enhance the learning experiences for students, senior-level undergraduate students who had already completed the two courses were employed to design, build, test, and modify the experiments. The authors developed the general concept of the experiment, identified the equipment that the experiments would be built upon, and guided the students through their work. The students, though, had primary responsibility for determining how best to design and perform the experiment, utilizing their familiarity with the concepts and their understanding of the course material. The students were in a better position to know what should be best emphasized in the experiments to help them, and other students, learn the material more completely. Therefore, they were relied upon to build the best experiments for the future students taking the courses. With this background in mind, the remainder of this paper will focus on describing the experiments centered on common hardware for the two courses, and then discuss the benefits and detriments of the approach taken. Refrigerator Experiment One experimental apparatus involves a standard 0.048-m 3 (1.7-ft 3 ) refrigerator. 4 This size refrigerator can be typically found in dormitory rooms, small offices, or any other location where P ge 11475.3 a small amount of space is available for a refrigerator. These refrigerators are typically of a very simple design. The Thermodynamics experiment that uses this set-up involves having the students determine the actual coefficient of performance of the refrigerator. The Heat Transfer experiment using this equipment involves the students using the equipment to study an example of free convection and an example of forced convection. The enclosed space gives an ideal location for performing such a controlled experiment, and from the experiments, the students are able to reinforce their understanding of the benefits of forced convection over free convection in a cooling environment. The Thermodynamics experiment could be performed with little modification of the basic refrigerator. The experiment is performed by placing a heated object inside the refrigerator so that a load is provided for the operation of the refrigerator. The temperature on the inside of the refrigerator is measured with thermocouples over time, and a power sensor measures the power consumption of the refrigerator. By measuring the temperature inside the refrigerator, the heat removed from the refrigerator can be calculated from the First Law of Thermodynamics. After set periods of time, the work done by the compressor is determined from the Watt Transducer measurements, and the coefficient of performance of the refrigerator can be calculated. This experiment helps reinforce the concept of the coefficient of performance for the students. While the Thermodynamics experiment could be performed on an unmodified refrigerator, the Heat Transfer experiment did require modification, and therefore both experiments operate on the modified refrigerator. The primary modification of the refrigerator was the insertion of a window in the door of the refrigerator and a light in the interior of the refrigerator to allow the students to visually see the air currents (as mapped by smoke trails) present during free and forced convection modes. The convection experiment also involved the placement of a cartridge heater into the refrigerator to provide the necessary steady load to the experiment. The forced convection part requires a fan to provide the moving air. These objects, plus associated measurement devices such as an anemometer, require a stand for support inside the refrigerator. Additional holes were needed in the refrigerator to provide an entry point for the wires needed to power the experiment inside the refrigerator. Pictures of the outside and inside of the Refrigerator Experiment are shown in Figures 1 and 2, respectively. During the convection experiment, the refrigerator is operating to provide a cool surface to offset the heated rod and generate some free convection movement as well as a means to remove the input heat from the system. The experiment begins after steady state is achieved. The free convection experiment is performed first, with temperature measurements taken over a 5-minute interval. The smoke is then added to the system, and the students are able to visualize the flow patterns. The fan is then started, and the system is operated again until steady state is achieved. Air speed and temperature measurements are acquired over a 5-minute interval, and the students then proceed to their calculations. In the calculations, the student

Development Of Experimental Apparatuses To Be Used In Two Sequential Thermal Science Courses