Rueil-Malmaison

Machine learning enhanced resolution of Navier Stokes equations on general unstructured grids

Computational fluid dynamics relies on the numerical resolution of the Partial Differential Equations (PDE) of the Navier-Stokes problem. To that end, we use spatial and temporal integration schemes to predict the evolution of physical fields representing liquid or gas phases inside a computing domain discretized by a mesh. To handle complex physical phenomena at small scales, either in time or in space, it may be necessary to manage several millions of grid cells and time steps of the order of microseconds that make simulation times very long even with parallel execution.

Coalescence in complex physicochemical systems

The mechanisms of coalescence is of huge importance in the process of soft matter and divided materials such as emulsions and foams. It controls their stability and their final properties in many applications including cosmetics, food engineering, energy, biotechnology etc. It has a significant influence in wastewater treatment. Actually oil removal relies on gravitational methods that are favored by coalescence. In Enhanced Oil Recovery, water treatment is all the more challenged by residual polymers and surfactants that constitute complex physico-chemical systems.

Methodology development for analytical modeling of hybrid vehicle’s electrical components: Energy performance optimization

The hybrid electric vehicle (HEV) is a complex system consisting of several energy sources. Depending on their configuration typically combining an internal combustion engine, electrical machinery and a storage system, significant benefits in terms of energy consumption as well as other  features can be achieved as compared to a conventional vehicle. In order to achieve this goal, optimization is required at different levels. For a given use, the energy performance of the HEV  mainly depends on three highly interdependent aspects:
-    The topology : series, parallel ...

Unravelling the genetic regulation of enzyme secretion in hypercellulolytic strains of the filamentous fungus Trichdoerma reesei

Industrial large-scale production of lignocellulolytic enzymes by Trichoderma reesei represents a major economic issue for ethanol production from lignocellulosic biomass. In particular, the capacity of this ascomycete to secrete large amounts of enzymes is primordial. Hyperproducing strains are able to develop an extended endoplasmatic reticulum if they are cultured in the presence of substrates which induce enzyme production.

Molecular simulations applied to lithium batteries

Background: In the light of sustainable mobility, batteries play an essential role in the electrification and hybridization of transport vehicles. Batteries based on lithium ions currently offers one of the best performances with respect to other rechargeable batteries. However, in lithium ions batteries solid electrolyte interphase (SEI) layers are formed that can severely impact the performance of these batteries if they use graphite-based electrodes.

Design of impact characterization factors adapted to the Life Cycle Assessment method for the evaluation of fuel emissions at altitude.

Renewable energies (RE) are the most suitable vectors to meet the imperatives of environmental protection and reduction of greenhouse gas emissions. The air transport sector is positioning itself on these new energies as part of its objective to stabilize CO2 emissions from 2020 onwards and then to reduce its CO2 emissions by 50% by 2050. However, the air transport sector is growing and it’s becoming a key issue to find sustainable solutions regarding the choice of fuels. Most of the air transport emissions occur at altitude during the aircraft's cruise phase.

Study of the damage mechanisms of formations during the reinjection of geothermal fluids

The reinjection of geothermal fluids after exploitation is often necessary to ensure the sustainability of the geothermal field both from an environmental point of view, via the storage of fluids produced by the exploitation, and from an economic approach by the maintenance of the pressure in the reservoir. These fluids are often loaded with mineral and organic particles in suspension, dissolved organic and inorganic compounds (salts), various additives, bacteria and / or heavy metals ...

Optimal sizing of distributed energy production / consumption equipment

Upcoming Energy transition should increase the level of investment in production/storage of renewable energy systems distributed within the electricity network. These investments are usually profitable after several years and their level of profitability is quite uncertain due to the stochasticity and the intermittency of renewable production.