At the University of Kentucky, an undergraduate course in the Chemical & Materials Engineering curriculum is offered and is called CME 425: Heat and Mass Transfer. Recently, the department has been making a concerted effort to bring more experimental applications back into the classroom. One such experimental series incorporated into the classroom environment is the study of unsteady-state heat transfer within simple geometries (flat plate, sphere, and cylinder). In this series of experiments, students apply fundamental principles of heat transfer to evaluate the change of temperature over time under conditions of natural convection. A single thermocouple wire is placed in the center of simple geometrical objects constructed of different materials. The object is suspended from a fiberglass rod and immersed in a hot water bath. Personal computer software coupled with a data acquisition board is used to capture discrete points as they vary with time across the temperature ramp. Various standard concepts are incorporated into the required semester project, including the Biot number, Fourier number, use of Heisler Charts [1], and thermal conductivities of different materials.
Concurrently, within the same semester, the students are taking another class called CME 420: Process Modeling. In this class, a semester project is assigned that requires analytical tools be applied to the experimental data acquired in the unsteady-state heat transfer experiment. Numerical series approximations (Fourier series solutions [2]) with use of Excel spreadsheets (Bessel functions) are prepared for comparison to collected laboratory data. Use of the numerical series approximations is especially interesting in that it gives students an opportunity to judge how many terms in the infinite series must be used to approximate actual unsteady state heat transfer in a specific application. Finally, students are exposed to more advanced software by using a finite element package (COMSOL Multiphysics) to model the unsteady-state heat transfer within a simple cylinder.
In summary, coordination of semester projects across two disciplines (heat transfer and process modeling) allows undergraduate students to purse an in-depth investigation of a special topic that would otherwise be too complex or lengthy to undertake within any single stand-alone engineering class.
Results and plots from these experiments will be presented at the AIChE Conference.
1. Heisler, M.P., Temperature Charts for Induction Heating and Constant-Temperature Heating, Trans. ASME, April 1947, pp. 227 - 236.
2. Schneider, P.J., Conduction Heat Transfer, Addison-Wesley, Reading, MA, 1955.