Developing Innovative Teaching Materials That Use Molecular Simulations in Engineering Thermodynamics

Abstract

Traditionally, Engineering Thermodynamics is presented to undergraduate mechanical engineering students from a classical viewpoint. The emphasis in the courses is on analyzing processes involving bulk thermodynamic properties of materials to ascertain the performance of systems of significant size such as internal combustion engines, steam boiler power plants, vapour compression refrigeration systems, gas compressors etc. This emphasis may need to change so that mechanical engineers gain a better understanding of areas such as nanotechnology, fuel cells, photovoltaic cells and solid state electronics. A further need for change, is because thermodynamics, as a subject, has a reputation that many students apply formulae in a rote-like manner and struggle to understand the underlying physics and practicalities. One of our innovations is to use simple one and two dimensional hard sphere simulations to demonstrate the validity of such basic constants as Avogadroâ¿¿s Number and the Boltzman constant, and then visually demonstrate the ideal gas equation explaining concepts such as temperature and pressure and the way in which they relate to the volume containing a specified number of molecules. The underlying mechanical/physical reasons for the idealizations and processes of thermodynamics can be visually demonstrated by simple hard sphere models in ways that are related to mechanics. We outline some examples of simple simulations and innovative teaching materials that model the molecular (microscopic) behaviour on which macroscopic thermodynamic behaviour depends. Initial trials of some of the ideas that have appeared in past congress papers have been or are currently being trialed. These trials have revealed how students tend to follow the â¿¿rote learning of formulae and procedure approachâ¿ rather than the â¿¿physical understandingâ¿ approach.