This paper outlines a simple particle mechanics model in which a single particle represents the thermodynamic fluid (gas) in a heat engine (exemplified by a piston engine). By mechanics based reasoning the model demonstrates the connection between the Carnot efficiency limitation of heat engines and the Kelvin-Planck statement of Second Law requiring only the truth of the Clausius statement.

In a recently developed simple particle mechanics model in which a single particle represents the working fluid (gas) in a heat engine (exemplified by a piston engine) a new approach was outlined for the teaching of concepts to thermodynamic students. By mechanics reasoning a model was developed that demonstrates the connection between the Carnot efficiency limitation of heat engines and the Kelvin-Planck statement of Second Law requiring only the truth of the Clausius statement. In this paper the model is extended to introduce entropy. Here the particle's entropy is defined as a function of its kinetic energy and the space that it occupies that is analogous to that normally found in classical macroscopic analyses.

The design and mathematical modelling of thermal radiator panel to be used primarily to measure night sky radiation wet coated surface is presented in this paper. The panel consists of an upper dry surface coated aluminium sheet laminated to an ethylene vinyl acetate foam backing block as an insulation. Water is sprayed onto the surface of the panel so that an evaporative cooling effect is gained in addition to the radiation effect; the surface of a panel then is wetted in order to study and measure the night sky radiation from the panel wet surface. In this case, the measuring water is circulated over the upper face of this panel during night time. Initial TRNSYS simulations for the performance of the system are presented and it is planned to use the panel as calibrated instruments for discriminating between the cooling effects of night sky radiation and evaporation.

Modern mechanical engineers need to learn more than the traditional classical approaches to thermodynamics and heat transfer. Matter is comprised of molecules and in many situations the behavior of these molecules may be modeled using hard spheres whose motion is governed by Newtonian mechanics. This is particularly true in those situations involving relatively low density gases, that are valuable in introducing the concepts of thermodynamics. This paper presents some models that have been developed using simple-to-use software that students can handle in a time-efficient way during class-room situations, using only Newtonian Mechanics. Experience indicates that students have many conceptual difficulties when studying engineering thermodynamics. Simple molecular dynamic approaches promise to give students a more intuitive understanding of these thermal areas.

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 Avogadro’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 “rote learning of formulae and procedure approach” rather than the “physical understanding” approach.