Abstract:

Thermodynamics is both a branch of physics and an engineering science. It began in the early nineteenth century through consideration of the capacity of hot bodies to produce work. Nowadays, its scope is larger and meets the objective of analyze and design energy systems to meet human needs as effectively as possible.

The complexity of the equations used to solve thermodynamic problems demand a high level of scientific knowledge not only in the field of thermodynamics but also in mathematics. There are currently numerous computer programs able to help in the management of those demands. Each of them presents some advantages and limitations, mainly determined by the way of focusing the problem. Roughly, they can be divided into two groups: the mathematical approach and the training-focused approach. Half way between both approaches, we have developed a simulation tool, ThermoGraf (http://termograf.unizar.es)) which achieves, through a highly interactive graphical interface, to solve virtually all of the problems that are considered in introductory courses in engineering thermodynamics at university level, without losing the friendly interface and mathematical precision.

A graphic environment with a high-interactivity level is created, allowing the user to manipulate the states and thermodynamic processes of the considered thermodynamic system, with the same ease as in a standard vector drawing program. This is not a trivial aspect, since the majority of its models for calculating properties of real substances only provide acceptable values in their limited range of use. Then, it was required to improve those models so that the graphical representation values compensate for the deficiencies of the original standards. There exists a main menu and a toolbar that allow nearly a hundred actions to be performed by selecting an option in the menu and then clicking on the mouse and dragging on the thermodynamics graph. As a consequence, the working procedure only takes some minutes to be learnt. The interface simultaneously displays graphical and numerical information of the system, providing full accuracy for the values of state properties, process information and mass and energy balances evaluation.

From the extensive experience acquired over more than twenty years working with the software TermoGraf, three years ago the possibility of going one step further was considered. The project of developing an application for mobile devices was raised and the design and development of the app Thermonator successfully started. The app can already be downloaded at google play: (https://play.google.com/store/apps/details?id=com.xmuzzers.thermonator&hl=en). It is an advanced thermodynamic calculator (for mobile phones and Android-based tablets) that makes the agile use of ICT resources plausible in the context of active methodologies during lectures. In addition, it can be used by students in their personal study and in group work. There exists an innovation project devoted to continue developing aspects of the app that are still pending and to deepen the application and analysis of its benefits in meaningful learning by students of Thermodynamics, a fundamental discipline in the scientific-technical training of the students.

Both the ThermoGraf experience in Thermodynamics courses at the University of Zaragoza (Spain) and the additional opportunities provided by the derived app, Thermonator, are presented in this paper.

Keywords:

Thermodynamics simulator, e-learning based on problems, TermoGraf, Thermonator.