PhD student in experimental and numerical study of the effectiveness of gaseous and condensed inhibitors on hydrogen flames (M/F)

Job Description

Thesis Subject

Hydrogen is an important lever for achieving carbon neutrality by 2050. In this respect, the French hydrogen plan aims at increasing the annual consumption of renewable or low-carbon hydrogen to 700kt by 2030 (out of 1,345kt), compared with 45kt/880kt in 2020.
To achieve this goal, the plan calls for the large-scale deployment of facilities for hydrogen production, storage, and use. However, this scenario poses a number of challenges in terms of safety. The risk of explosion from hydrogen leaks, whether chronic or accidental, could act as a brake on our capacity to fully deploy the hydrogen-based technologies on short terms, especially as conventional mitigation measures such as ventilation or recombination may not be sufficiently effective for certain cases. Flame inhibition remains a promising solution for limiting the consequences of hydrogen explosions. This involves injecting products capable of reducing the chemical reactivity of the flammable mixture when hydrogen is detected.
Despite the undeniable scientific and practical interest of flame inhibition, the related literature studies remain scarce in the case of hydrogen. The CHAIN-H2 project proposes to extend our fundamental knowledge of the chemical mechanisms responsible for inhibiting hydrogen flames. To achieve this, the CHAIN-H2 project will combine experimental and numerical studies covering small-scale kinetics through to modelling of the larger-scale characteristics of flame inhibition (flame propagation in a cloud of particles). The inhibitors considered will be mixtures of chemical (sodium and potassium bicarbonates - NaHCO3 and KHCO3) and thermal agents (CO2/N2) in the form of propellant gases. The ultimate aim of
the project is to establish an experimental and numerical database for characterizing the effectiveness of inhibitors in the event of accidental hydrogen leaks in industrial-type configurations. The ANR CHAIN-H2 project brings together a consortium comprising the French Nuclear Safety and Radiation Protection Authority (ASNR), the European Center for Research and Advanced Training in Scientific Computing (CERFACS), and the Institute for Combustion, Aerothermal Reactivity, and Environment (ICARE), a unit of the French National Center for Scientific Research (CNRS), aims to expand knowledge of the chemical mechanisms responsible for hydrogen flame inhibition.
To do this, CHAIN-H2 will combine experimental and numerical studies covering small-scale kinetics to the modeling of larger-scale characteristics of flame inhibition (flame propagation in a particle cloud). The inhibitors considered will be mixtures of chemical agents (sodium and potassium bicarbonate) and thermal agents (CO2/N2) as propellant gases. The ultimate goal of the project is to establish an experimental and numerical database to measure the effectiveness of inhibitors in the event of accidental hydrogen leaks in industrial-type configurations.
As part of this project, the thesis will focus, on the one hand, on a detailed analysis of gas phase inhibition kinetics by combining experimental and numerical studies to determine global parameters (auto-ignition delays) and detailed parameters (species profiles) in shock tubes. On the other hand, the impact of gaseous and solid inhibitors on accelerated flames will be elucidated. To do this, experiments will be conducted in the ENACCEF-2 vertical flame acceleration tube. The effectiveness of gaseous and condensed inhibitors (N2 and CO2) on hydrogen flames will thus be characterized.

Your Work Environment

The thesis will be affiliated with the Doctoral School of Energy, Materials, Earth and Universe Sciences. The ANR CHAIN-H2 AAPG2025 – CES 05 project brings together a consortium comprising the French Nuclear Safety and Radiation Protection Authority (ASNR), the European Center for Research and Advanced Training in Scientific Computing (CERFACS), and the Institute for Combustion, Aerothermal Reactivity, and Environment (ICARE), a unit of the National Center for Scientific Research (CNRS), aims to expand knowledge of the chemical mechanisms responsible for inhibiting hydrogen flames. The main place of work is at the ICARE laboratory in Orléans, within the Energy Systems Kinetics and Dynamics team led by Dr. Comandini. Travel to the ASNR and CERFACS will be required.

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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