FRAISE project intends to optimize energy conversion through falling-film absorption processes. Its main technological outcome is the development of innovative concepts for the design of efficient desorbers, which represents the bottleneck for the conception of new compact absorption machines adapted to automotive air-conditioning, and more generally to the design of efficient heat pumps, chillers and recovery systems to limit energy waste. The project focuses on the automotive application for which compactness is crucial. Yet, the investigated design solutions will benefit to the development of compact absorption machines adapted to abundant low-grade temperature sources (industrial waste, marine transports) and renewable energies (solar cooling, domestic heating). Desorbers are key elements of the absorption machines where coupled heat and mass transfer occur. The correct sizing and the compactness of these components represent the principal challenges to the aimed technical application. We propose to develop new concepts of desorbers using plate exchangers with falling films, which have the advantage to be easily operated in vacuum conditions as required whenever low-temperature heat sources are considered. In this project, we propose to optimize and control the wavy motion of a falling film in order to intensify heat and mass transfers across the film. Indeed, it is known that the mixing and surface renewal mechanisms generated by surface waves may enhance heat and mass transfer rates several folds. This project is thus devoted to the wavy regime that mostly develops at moderate Reynolds numbers. Passive control by means of wall corrugations will be considered and tested under external vibrations. The design of new strategies of transfer intensification requires (i) to understand how the wavy dynamics is affected by the coupling with the transfer due to the induced variations of physical properties at the free surface, (ii) to identify the most efficient wavy structures and their optimum dynamics (rates of creation and merging, spatial and temporal distribution etc.) to promote transfers and (iii) to propose efficient strategies to control the hydrodynamics of the flow, generate these wavy structures and their distribution in time and space and to test these strategies under external vibrations. To meet such requirements, we propose a strategy combining an advanced fundamental research effort and a latter-stage more applied study with the adaptation of a dedicated prototype of absorption machine and a test campaign on an experimental bench developed by the industrial partner. This exploratory project, oriented to fundamental research combine theoretical and numerical approaches based on direct numerical simulations (DNS), advanced shallow-water mathematical modelling and thermodynamic modelling at the component and system levels, to experimental studies using avant-garde non-intrusive optical techniques, and in particular, a two-colour Laser-Induced Fluorescence technique that will be adapted to to measure in-depth temperature gradient across the wavy film. The project will take advantage of the skills of three complementary laboratories in the field of Heat/Mass Transfer using specific non-intrusive optical techniques (LEMTA), Applied Mathematics and shallow-water approaches (LAMA/LOCIE) and Engineering with the design of absorption machines (LOCIE). The projects benefits from the involvement of the industrial partner (PSA) (two already financed test benches, one of which at PSA). The synergy between the theoretical and experimental investigations will be fostered by the proximity between two partners (LOCIE and LAMA on the same campus) and the regular meetings of the informal CNRS group GDR FILMS.

In the foreseeable future, the adoption of multifunctional car structure (MCS) will offer the potential to radically upgrade the abilities of vehicles in terms of ecological requirements emerging from the social and legal environment. Integrating car structures with functional systems that monitor structural integrity and aging, change shape at local level, act as sound sources and tackle noise vibration harshness issues will eliminate many of the weight, volume, and signature penalties associated with the current approach of designing, manufacturing and maintaining vehicles and functional systems separately. Current cars already have a structure optimized to have low weight without reducing the required performances. However, by means of MCS structural components can be further reduced in weight without compromising resistance, crash and fatigue performances while still offering more advanced functionalities. One type of MCS that appears as very promising and which we propose to investigate in this project is a Load-bearing Loudspeaker Structure (LLS). A LLS refers to structures that are equipped with active elements such as piezoelectric elements that allow for sound spatialization and noise and vibration control. In terms of integration, LLS structures may easily be retrofitted to existing car frames (interior or exterior) or incorporated within new platforms. As acoustics plays a key role in automotive design, a widespread use of LLS will enhance vehicle security and comfort. Indeed, on the one hand, auditory warnings are vital in the automotive world in attracting attention and conveying information to the driver. Auditory warning alerts reduce the distraction of the driver from his primary driving task and therefore enhance the safety. Spatial restitution of warning signals is furthermore directing the attention of the driver directly towards the danger. It provides a more intuitive way of conveying information and better interaction with other human-machine interfaces. We intend to excite these surfaces to generate and spatialize auditory warnings. On the other hand, wave field synthesis with a reduced number of loudspeakers will allow us to produce more realistic sound inside the passenger cabin, which is becoming increasingly important in entertainment systems in partially autonomous and autonomous cars. In summary, this project proposes to functionalize the surfaces present inside the passenger cabin of a car in order to enhance vehicle security and comfort by addressing the following scientific and industrial issues: Based on a system and user requirements evaluation the figures of merit of such a new class of loudspeaker will be determined. Then, special low energy piezoelectric transducers will be designed that allow covering the whole audio frequency spectrum. A main research area will address the high amplitude requirements at low frequencies. In order to compensate for sound panel non-linearities, active control strategies for sound improvement and surface vibration mitigation will be designed. Those surface loudspeakers will be integrated into a test car, once they achieved sufficient robustness and sound quality. Equalization and compensation methods will be applied to guarantee perfect equilibrium of the sound. In a first step, the efficiency of the whole system will be deduced from user-centred evaluations compared to a traditional loudspeaker set-up. In a second step, after several iterations a more complex sound scenario based on 3D sound field reconstruction will be implemented into the test car. Qualitative ratings of this second system will be extracted from a second user study.

In the field of transportation, vehicles (ground or air) are becoming more and more autonomous and communicating. The emergence of these new technologies may relegate pilots to a supervisory role, implying less vigilance and less awareness of the environmental context. This degraded state can hinder the effective recovery of the vehicle and lead to dangerous situations. The objective of the COMMUTE project is to develop a genuine non-verbal, multimodal, intuitive and interactive communication system between the driver and his vehicle. For this purpose, multimodal solutions based on a cognitively situated approach will be developed within the framework of an interactive multimodal synthesis platform. Two use cases, presenting a strong safety issue, will constitute the common thread on which theoretical and experimental developments will be based: emergency warning (short time) and continuous regulation (long time).

The increasing number of power electronics devices in an automobile and their impact on the vehicle's electrical network impose increasingly stringent constraints in terms of reliability and safety. Car manufacturers are now faced with two major concerns: they must ensure compliance with standards limiting spurious emissions from the car and respect for the exposure of people to electromagnetic fields (EM) within the vehicle and they must guarantee the proper functioning of all equipment in a normally polluted EM environment. The stakes in the vehicles of tomorrow go beyond these aspects through the vulnerability to EM aggressions of autonomous driving systems. Indeed, wiring and I / O are all possible input vectors for disturbances to malfunction of the guidance or for eavesdropping to spy on the condition of the vehicle. It is therefore essential to know how to install these new equipments without risk to their immediate environment and to master the devices allowing their protection. The electromagnetic compatibility (EMC) between the equipment is ensured on the one hand by means of installation rules designed to minimize the coupling with the power circuits, but also by the obligation that these equipments have to comply with standards that limit Radio Frequency interference emissions and make the systems robust to external aggression. This is why the EMC study of a vehicle must today be an integral part of the development of a vehicle and must intervene at the beginning of the design phase of the vehicle. This would provide a significant competitive advantage in view of lower costs and development time. We can also mention the possibility of normative constraints that may be more restrictive and thus help to preserve the markets of less well designed and riskier devices. The determination of the EM performance of complex systems of current and future vehicles is the main obstacle to the deployment of new technologies (guidance, electric propulsion ...). All project partners aim to overcome this blocking point. EMC optimization of complex systems such as a complete vehicle therefore requires the development of sophisticated modeling methodologies. Consequently, it is fundamental to prepare this technological evolution and to propose simulation approaches dedicated to complex systems. System-oriented modeling has improved considerably over the last twenty years, both in the fineness of description of electric and electromagnetic models and in the available computing power. However, the direct use of existing tools for the analysis of a large system, taking into account the strong interaction between subsystems, has not progressed. It is therefore imperative to exchange the different models of the subsets because no method will allow a complete modeling of an industrial system. The cornerstone of the approach proposed in this project is to implement a network co-simulation methodology in order to mobilize simultaneously and distributed the set of parcel models necessary for a complete system modeling. In this approach the different models are neither shared between partners nor integrated into a single tool but communicate in real time through their interfaces. To achieve such a co-simulation it is obviously essential to remove certain locks relating to the models relevant to the different subsets, but it is also essential to make these different elementary bricks coexist and communicate in the same simulation through exchange of relevant data.

The STELLAR (SusTainable mEtaL fueLs for future trAnspoRtation) project intends to demonstrate the viability of new energetic carriers. Based on both energy and transportation sector requirements – such as autonomy related to weight or volume, easy refill, cost, distribution and storage – metal powders appear convenient as renewable alternative fuels. Indeed, they can burn to release heat without any carbon chemistry, and can be regenerated by thermochemical processes powered by renewable sources. This has the potential to create a major breakthrough in addressing renewable energy storage issues, climate change, and transport fuel costs, in accordance with mid-to long-term French government expectations. Promising recent studies performed by the project stakeholders mitigate the inherent risks that could be encountered by this breakthrough proposal in terms of targets and barriers. This works propose an distinctive approach to solve on the long term the energy storage and the climate change mitigation issues. This enhances STELLAR’s investigations to overpass a Technology Readiness Level 3. The project will aim to endorse several significant breakthroughs: capability to control the combustion of the particles so that the heat generated is practicable for a dedicated thermodynamic converter; designing of trapping on board 100% of the oxidized particles; and improving the processes to produce and regenerate particles using concentrated solar energy. Appropriate converters will be studied in order to match the specificities of the heat source with different transport applications. Furthermore, a life cycle assessment of the technology will position the concept in terms of Green House Gas emission, energy request and expected cost. The outcome of this multidisciplinary project will provide valuable answers to the major problem of energy storage and will serve as a basis for industrial developments in several key sectors (energy, automotive, aeronautics, metallurgy).