Manufacture of an ortho-para H2 sensor based on thermal conductivity and calibration of this sensor on binary gas mixtures

Institut Mines-Télécom is the leading public group of engineering and management Grandes Écoles in France. Consisting of eight public graduate Grandes Écoles and two subsidiary graduate schools, Institut Mines-Télécom leads and develops a rich ecosystem of partner schools, economic, academic and institutional partners, key players in education, research and economic development.

Mines Saint-Étienne, a graduate school of the Institut Mines-Télécom, is responsible for education, research, innovation, industrial transfer and scientific culture dissemination. With 2,500 students, 500 staff and a budget of €50m, it has 3 campuses dedicated to the industry of the future, health and well-being, and digital sovereignty and microelectronics. It is ranked in the top 15 graduate engineering schools in France and the top 500 universities worldwide.

The 2023-2027 strategy of Mines Saint-Etienne is in line with that of Institut Mines Telecom. It aims to:

• Support the ecological, digital and generational transitions and educate the people involved
• Support national and European sovereignty in microelectronics and digital technology

Presentation of the center: The SPIN (Science des Procédés Industriels et Naturels) center, where the internship will take place, develops its expertise in process engineering applied to dispersed systems (grains, particles, droplets, bubbles, porous media) at Mines Saint-Etienne. It also has expertise in sensors and instrumentation development.

The internship will be carried out in collaboration with the NEEL Institute and the ALFA LAVAL group.

The NEEL Institute is a condensed matter physics research laboratory located in Grenoble. It is a CNRS research unit (UPR 2940) created in 2007 with research themes focusing on magnetism, photonics, quantum electronics, quantum fluids, and superconductivity. The institute has particular expertise in cryogenics and the technical framework for conducting hydrogen measurement tests under cryogenic conditions.

ALFA LAVAL, a world-renowned expert in the design, manufacture, installation, and maintenance of brazed heat exchangers, cold boxes, core-in-drums heat exchangers, and Cryomec® cryogenic pumps, will also be involved in the project. In particular, it will contribute its expertise in the field of cryogenics and enable the sensors to be tested in industrial facilities.

As part of an ANR-funded project related to current energy challenges, a 6-month internship focusing on the manufacture and calibration of an ortho-para H₂ sensor based on indirect measurement of thermal conductivity is offered here. This sensor will not be calibrated for H₂ during this internship but during the thesis that will follow the internship. During the internship, the focus will be exclusively on characterizing binary gas mixtures with similar thermal conductivities (N₂/O₂ and N₂/CO₂), which will enable the sensor's performance to be validated under conditions that are easier to implement.

Presentation of the internship's tasks and activities:

• Manufacture of the sensors and micro-heaters required for binary mixture composition measurement (screen printing, laser engraving, validation of the protocol by measuring the resistance of the “sensors” and “micro-heaters”) and estimating the uncertainties associated with these values, binocular/optical microscope verification of the integrity of the microstructure.
• Instrumentation: creation of a Labview program that will enable the generation of power signals on the micro-heaters as well as the simultaneous measurement of sensor signals. Use of a Wheatstone bridge, in particular for measuring small relative variations in sensors’ resistances.
• Creation of an experimental glass cell equipped with sealed passages for the stoichiometric characterization of binary gas mixtures: N₂/O₂ and N₂/CO₂.
• Identification of the effect of test conditions (nature of the power signal: pulse/step/ramp, signal amplitude, micro-heater/sensor distance, etc.) on measurement accuracy.

• In the final year of engineering school or a master's degree
• Ideally within a master's degree program with one or more of the following specializations: fluid mechanics/transfer, thermodynamics, automation, sensors, and instrumentation
• With a strong interest in experimentation
• Digital skills are a plus (particularly Python coding)
• Versatile in a highly multidisciplinary field
• Strong oral and written communication skills (particularly in English)