Development, Characterization, and Assessment of Low-Cost, Hands-On Educational Tools for Improving Understanding of Heat Transfer Phenomena.

다국어 초록 (Multilingual Abstract)

Active learning is widely recognized as superior to traditional passive, lecture-based techniques for fostering learning in STEM courses. Interactive, hands-on learning where students interact with their peers and physical systems is an effective type of active learning. As the need for scientists and engineers continues to grow, understanding and incorporation of interactive learning pedagogies into STEM classrooms is critical. This dissertation is focused on the development, characterization, and assessment of very low-cost, visual hands-on learning tools which can be used to demonstrate and foster understanding of complex heat transfer phenomena in undergraduate engineering courses. First, the performance of a miniaturized double pipe heat exchanger is presented. Behavior can be predicted highly accurately with industrial correlations and results from conceptual and motivational assessments show the heat exchanger helps improve understanding and is well-received by students. Next, the effectiveness of the double pipe heat exchanger is compared to the effectiveness of a simpler module for demonstration of basic fluid mechanics principles. Two module implementation modes are compared: in-person and virtual demonstration. Hands-on and virtual implementations are shown to promote similar improvements in student understanding, highlighting the usefulness of the learning modules and other hands-on learning pedagogies in resource-limited or distance-based education settings. The double pipe heat exchanger module is shown to be significantly less effective for promoting conceptual understanding gains compared to the simpler fluid mechanics module and reasons for this are discussed. Finally, the development and characterization of a new module to demonstrate evaporative cooling, which is a complex heat and mass transfer process used in several industrial and residential processes, is detailed. The behavior of the device is evaluated with a fractional factorial design, compared to performance trends observed with larger-scale systems, and a new numerical model for prediction of water and air temperatures and performance is presented. Overall, the miniaturized evaporative cooler is shown to behave similarly to large-scale systems, highlighting its usefulness as a classroom teaching tool.