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Mécanique Appliquée : Study and modeling of the intermetallic powder bed behavior for hydrogen storage

Job Description :

The DMA has been involved in the topicof hydrogen storagefor 20 years, in the field of mechanics and materials sciences, activities now integrated in the Mat’éco team, Materials for the ecological transition.The main themes envisaged concern storage solutions under compressed form (filament winding, composite materials) and in so-called "solid" form(by formation of metal hydrides).

Candidate Profile:

The successful candidate will have good knowledge in mechanics and materials science.During these 3 years of doctorate, he will have to use and develop his skills for experimental characterizations, but will especially have to be involved in the implementation of the DEM tool (Yade). We are therefore expecting a candidate with predispositions and a proven taste for numerical modeling and code development, mastery of the Linux environment is a plus.Openness and involvement are major assets for success.

ENERGIE : Study of the interaction between the fuel cell and the static converter in the event of electrical or electrochemical failures: modeling, diagnostics and robust and fault-tolerant controls

Job description : Fuel cell electric vehicles (FCEVs) use the Proton Exchange Membrane Fuel Cell (PEMFC) as the primary source of energy and an energy storage system (battery or supercapacitors) to provide powerelectricity. To improve the lifespan of fuel cells and reduce the cost of FCEVs, a high-efficiency power converter, based on wide band-gap components (GaN or SiC depending on the voltage and power levels envisaged) and with enhanced reliability is essential for connecting the PEMFC to the vehicle's DC bus.

Keywords : Hydrogen Fuel Cell, Power Electronics, SiC/GaN Semiconductors, Diagnostics, Experimental TestBenches

Candidate profile : Candidate with broad knowledge in power electronics and hydrogen fuel cells in the context of electro-mobility

TF : High-stability microcell-based optical frequency reference

Keywords : Miniaturized optical clocks / MEMS alkali vapor cells / Time-frequency metrology

The interrogation of an alkali vapor atom ensemble in a mm-scale cell has allowed the development of a wide variety of high-precision chip-scale atomic devices [1], including in particular miniaturized atomic clocks [2]. These miniaturized microwave atomic clocks have known a remarkable development and progress, including their commercialization [3,4], and are attractive candidates for many applications due to their unrivaled size-power-frequency stability budget with a volume of 15 cm3, a power consumption of 150 mW and a fractional frequency stability of about 10-11 at 1 day integration.

Host laboratory : FEMTO-ST (Besançon, France)

Candidate Profile: The candidate should have a Master 2 degree or diploma from an « Ecole d’Ingénieur ». He (she) should enjoy applied physics sciences. A background cursus with knowledge and even know-how (through lab works for example) with clean room facilities and MEMS technologies would be appreciated.Additional knowledge in atomic physics, optics, electronics and instrumentation is also a plus-value. He (She) should enjoy team working.

Applied Mechanics : Optimization, fabrication and characterization of wood/natural fiber composite hybrid laminates

Framework of the project : The PhDis part of the transverse project WooFHi (Wood/natural Fiber High homogeneity/performance composite) carried by three laboratories of BourgogneFranche-Comté (LaBoMap -Cluny, FEMTO-ST -Besançon, DRIVE -Nevers). This project aims at optimizing and homogenizing heterogeneous and variable wood-based materials by layering and hybridization with natural fiber composites. The targeted structural applications concern the transport field.

Context : One of the methods to better control the mechanical properties of wooden structures is to use reconstituted materials, such as CLT (Cross Laminated Timber) or LVL (Laminated Veneer Lumber). In the latter case, thin layers of wood (veneers) are obtained by peeling a log, and assembled to obtain homogenized properties. But even in this case, the mechanical performance remains very variable compared to synthetic materials, and their use requires high safety factors. This limits their applicability in fields such as transport where the dimensioning must be done as accurately as possible in terms of weight/volume..

Starting job : 01/10/2021

Adress Host Laboratory : LABORATOIRE DRIVE - 49, rue Mademoiselle Bourgeois-58 000NEVERS &  FEMTO-ST –DÉPARTEMENT MECANIQUE APPLIQUÉE 24 Chemin de l’Epitaphe -25000 BESANÇON

Contact: 

Please send the following documents (all in one PDF file) by e-mail to Jérôme Rousseau – jerome.rousseau@u-bourgogne.fr:

1) For EU candidates: Copy of your national ID card or of your passport page where your photo is printed.For non-EU candidates: Copy of your passport page where your photo is printed.2) Curriculum Vitae (1 page).3) Letter of motivation relatively to the position (1 page).4) Copy of your Master degree and/or Engineer degree if already available.5) Copy of your final marks and ranks.6) Coordinates of reference persons (maximum 3, at least your master thesis supervisor): Title, Name, organization, e-mail.If you have questions regarding the application, please contact the supervisors

 

+ d'infos :
PDF icon offre_de_these_drive-femto_projet_woofhi.pdf

AS2M :"Modeling and control of the Dielectric polymer actuator based soft robotsusing the port Hamiltonian approach"

Context/ Aim :
This thesis will take place within the AS2M (Automatique et Systèmes Micro-Mécatroniques) department of FEMTO-ST Besançon.The main objective of this thesis is the design, modeling and control of the soft robotic structure to fast pick-put variable form objects using the energy based-approach called the port Hamiltonian approach

Detailed Description :

In this thesis, we are interested on the modeling and control of the soft robots based on the Dielectric polymer actuators. The Dielectric polymers have been developed in recent years and drawn the attention of the robotic community thanks to their different advantages: large deformation, fast response, energy efficacy and free materials, etc. Motivated by the multi-physical, nonlinear and distributed aspects of this system, the port Hamiltonian formalism will be used for the modeling and the control design.

Advisers :

Pr. Yann Le Gorrec, Dr Yongxin Wu, Dr Kanty Rabonorosa

Please find more details in the attached file.

Contact: 

Yongxin WU

yongxin.wu@femto-st.fr

 

+ d'infos :
PDF icon subjectthesis_anglais.pdf

Applied Mechanics : "Understanding the mechanisms behind the tactile perception of micro-textured surfaces"

Context : Most of our daily interactions with the environment are based on tactile exploration. Tactile perception relies on the stimulation of mechanoreceptors in the skin and on the processing of the response induced by the brain. So far, only few studies have been devoted to uncover the overall "perception chain", i.e. from mechanical stimuli, via signal conversion and transmission, to higher order neural processes related to the interaction of the human body with the touched surface. Surprisingly, most research in the field of sensorimotor control has ignored the mechanical characteristics of the surface in contact with the body. At the same time, most studies in the fields of surface engineering and mechanics have ignored the brain mechanisms involved in the processing of tactile inputs. This is a serious limitation in understanding the sense of touch.

Description  : This Phd work is part of the ANR COMTACT project bringing together 6 laboratories and whose objective is to "decipher" how the brain constructs tactile perception according to mechanical stimuli and responses of skin mechanoreceptors. The PhD works, bilocalised Femto-ST / LaMCoS (INSA-Lyon), concerns the identification of mechanical descriptors relevant for the tactile perception of micro-textured surfaces, and will begin in September 2021.

All the information you need to apply is specified in the attachments.

MN2S : "Behavior and durability of protonic ceramic electrochemical cell (PCEC) integrated" in a stack

Context :To ensure the energy transition, the use of hydrogen as energy vector appears to be an unmissable solution. Production of green hydrogen by the use of electrolysis process prevent formation of CO2 gases. In this context, solid oxide electrolyser, which presents high efficiency, is considered as promising production methods [1].

Job description : The works carried out during this PhD will be based on the ICB’s achievements in the fabrication of cells for PCFC and PCEC applications and electrochemical tests management. Three main areas will be addressed.

The first will involve the shaping of large (diameter 5 cm) and button cells (22 mm diameter) for PCEC. This step, essential for the following, will be carried out by successive band casting of the different layers (electrodes and electrolyte) and will be based on the WO 2014057218 A2 patent [4]. Multi-stage sintering will be realised due to the high temperatures required to densify protonic conductors. Deposition of these electrolytes by reactive magnetron sputtering on an anodic medium may also be considered [5]. The second part will focus on the realization of  electrochemical characterization using the Fiaxell test bench Technologies acquired recently by our team. The results obtained in this section will allow to understand the mechanisms during the operation of a electrolysis cell and will specify the key steps that lead to the performance of PCFCs. Finally, the third part will focus on integration of larger cells to produce a two cells stack. By testing it in real conditions, information on the compatibility, the stability and the durability of the materials core components of PCEC will be highlighted.

Application deadline : 1/06/2021

ENERGIE : Study of electromagnetic compatibility of a hydrogen fuel cell coupled to a very high frequency GaN-based power converter with advanced functionalities

The idea of the proposed PhD thesis subject is to study the integration and the frequency behavior of a GaN-based static converter coupled to a hydrogen fuel cell integrating advanced diagnostic functionalities of the state of health of the cell and of the converter. The study of the electromagnetic compatibility (EMC) of the Hydrogen Cell / GaN converter assembly aims to obtain the frequency analysis of the assembly knowing that in a context of integration, the parasitic elements (parasitic inductance, capacitance coupling) can interfere with the operation of the system. It will be interesting to check that the high measurements necessary for piloting and diagnosis are not disturbed by electromagnetic phenomena. An EMC theoretical study as well as a prototype of a GaN-based power converter strongly integrated on a 500W hydrogen fuel cell will be made. The EMC chamber is used to test the hydrogen fuel cell / GaN-based power converter to verify that it meets current standards for electromobility.

Host laboratory  : FEMTO-ST, Equipe SHARPAC, Plateforme Hydrogène – Energie, Rue Edouard Belin, 90000 Belfort Cedex

Contract duration : 36 mois

Application deadline : 15 June 2021

ENERGIE/RECITS : An economic analysis of decentralised electric systems incorporating hydrogen-energy

The low-carbon energy transition requires a deep transformation of energy systems in order to support the development of renewable but intermittent energy sources. Two energy vectors appear central in that matter: electricity and hydrogen. The access to energy is currently designed through a centralised management of energy transmission network with flexibility and balancing supply relying on mechanisms implemented by the transmission system operator. However, the large introduction of variable renewable energy sources (VRES) in the energy mix, as well as the implementation of decentralised energy systems (the so-called “micro-grids”, which are not always connected to the power grid) increasingly require to think about a local management of energy systems and their flexibility. Hydrogen which allows storing energy on a large scale and for long periods of time, appears as a promising energy vector in order to provide stability and flexibility of decentralised power systems. By contributing to a further development of VRES (through energy storage and supply of flexibility), and by providing an alternative to fossil fuels, hydrogen-energy may be a mean to meet social demand for low-carbon energy systems.

This is precisely the objective of the ISITE-BFC PATH project to analyse the technical feasibility and the economic as well as environmental and social interest of such energy systems incorporating hydrogen-energy, especially in the Burgundy and Franche-Comté region. A “hydrogen territory” label has been given to this latter, which resolutely intends to become a leader in that matter. Thus it appears as a relevant location for investigating how efficiently hydrogen could be introduced in energy systems, with experiments that might be replicable in other locations. This geographical context as well as the multidisciplinary orientation of the PATH project, that combines skills in engineering sciences and economic and social sciences, constitute the framework of the PhD work.

‍The doctoral research program will aim at analysing the value associated to energy storage and provision of flexibility for electricity networks, through energy production and distribution devices incorporating hydrogen-energy within the framework of a decentralised territorial perspective.

NB : the doctoral student will belong to the SEPT doctoral school

Adress Host Laboratory:  FEMTO-ST : Rue Thierry Mieg, 90010 Belfort Cedex, France & CRESE, 30 Avenue de l'Observatoire, 25009 Besançon, France.

Candidate profile:Economist or engineer with a master degree in economics - Skills in modelling - Good knowledge of energy and electricity systems

An experience of qualitative research will be appreciated and skills in French language are required for interviews with local actors implementing energy systems based on hydrogen in French regions.

Deadline : 15/06/2021

ENERGIE : State of health and Remaining Useful Lifetime estimation for fuel cell systems

Context :

The fuel cell systems still suffer from low reliability and durability, besides the high cost. The objective of the RESYLIENT project is to develop algorithms to characterize online, realtime the operation (performance), the state of Health SoH (diagnostics) and the Remaining Useful Lifetime, RUL (Prognostics) of a PEMFC. The developed algorithms are mainly signal based using the major approach of signal processing approaches for SoH determination of the stack, online under dynamic load profiles. Besides, in automotive systems sensors are exposed to rough environmental conditions like extreme temperatures, wet and dry humidity, ice formation, vibrations, and shocks. This leads to frequent failures in sensor signals.

Objectives of the PhD thesis

The goal of this thesis is to develop simple models to increase the durability of FC systems (diagnosis, prognosis, fault tolerance) taking into account the real integration constraints of the system, in the design of the algorithms themselves; that is to say, to take into account the constraints related to embedded systems where one needs to operate a reliable diagnosis/prognosis without stopping the system, and without using intrusive, bulky, or expensive sensors or devices.

It would be interesting to apply different approaches for the analysis of non-stationary signals from PEMFC fuel cell systems to develop reliable fault tolerant diagnostics, prognosis and control. We are particularly interested in the analysis of response to multi-frequency signals. It will therefore be necessary to establish a solid theoretical basis for the signal processing tools to be used, and then apply them to databases from experimental tests. In parallel, accelerated test protocols must be set up and will allow to validate the developed algorithms.

Qualification: Master Degree

The PhD applicant should: Hold a master’s degree or equivalent and have competencies in one or several of the following topics: electrical engineering, electrochemistry, automatic control, computer sciences, Applied mathematics, data mining, artificial intelligence.

• Have good written and oral communication skills in English.

• International applications are strongly encouraged.

Deadline : 15/05/2021

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