Energy and Thermal Centre of Lyon

The fields of application of the research activities of CETHIL are very varied, from refrigeration to engines, from microelectronics to housing.

CETHIL is a Mixed Research Unit, the activities of which are totally geared towards thermics and its application to energy systems. CETHIL deals with issues relating to:

1. the physics of heat transfer. The aim is to understand, characterise, predict and control the phenomena that govern heat transfer and its coupling, at different scales (micrometric, nanometric to large scales such as in building) and via all means of transfer (convection, conduction, radiation, phase change)

2. thermics in complex systems and their energy efficiency: thermics in construction or energy systems (refrigeration systems, engines and combustion chambers, solar systems etc.)

3. the processes governed by heat transfer, in particular plastics engineering processes.

The laboratory has identified five major subjects which revolve around a great many important scientific and societal issues that ten research groups comprising work teams and competence centres are seeking to resolve. Each group is developing a strategy shared equally between theoretical studies and experimental work. The former lead to the creation of models and codes, while the latter are conducted thanks to a range of highly effective and original means, for the most part in France, and often recognised internationally.

These physical resources and competences enable CETHIL to publish each year more than one hundred articles in scientific journals with a reading committee and at international conferences.

This is why the fields of application of the research activities of CETHIL are very varied, from microelectronics to engines, from the study of nuclear materials to housing.

"Reactive environments and radiation transfer"

The aim is to increase knowledge in the field of heat transfer that can be induced by physicochemical combustion processes or that is produced by radiation in complex anisotropic and heterogeneous environments. Ascertaining the thermophysical properties of the environments plays an essential role, in particular for all modelling and simulation activities, with a view to optimising the systems or processes.

"Transfer and physics of materials"

All the work carried out on this theme aims to model and optimise the thermal behaviour of polymer materials and composites, in particular with regard to the relationship between their physical structure and their thermomechanical behaviour.

"Transfers in fluids"

The studies developed for this theme are based on heat transfer with or without phase change, and their application to various energy or heat systems. The main areas looked at are refrigeration machines, heat pumps, heat pipes, and technical objects that need strict control of heat transfer in order to operate correctly. The overall performance of many systems depends on the flow characteristics near the wall. Energy performance is improved by way of various coupling mechanisms that involve a fluid/solid interface: developing aerodynamic instability in the presence of confinement effects (limit layers, jets etc.), controlling the temperature of the wall to promote the development of convective instability etc.

"Small scale transfer"

New technologies have now made it possible to create nano-objects and nano-structured materials used and highly sought-after for the manufacture of new insulating materials, electromechanical systems, electronic components etc. The reliability of these systems depends, among other things, on their properties and their thermal or electromagnetic behaviour, which are being studied specifically with regard to the above-mentioned aspects.

"Energy performance of buildings and solar systems"

As part of the ongoing efforts to reduce greenhouse gasses and save energy, research is being carried out here on this subject with the aim of developing highly efficient solar and energy storage technologies as well as fostering understanding and acquiring control over the heat behaviour in buildings as a whole, including with regard to their relationship with the environment. The studies have been broken down into several levels, from fundamental physical phenomena (in construction materials, in storage systems and materials used for storage, at the scale of charge carriers in photovoltaic cells etc.), through to global models capable of providing a simple and reliable description of systems, of the building, and even of its environment (urban heat islands, the thermics of a district etc.).

Subjects

Radiation transfer and coupling in semi-transparent environments; thermics in reactive environments; thermics in polymers and composites; transfers with liquid-vapour phase change; energy performance of heat and refrigeration systems; convective transfers; micro and nano-thermics; thermal solar energy and photovoltaic energy; storage; the thermics of buildings in their environment