Papers by Christophe Proust
International Conference on Multimedia Information Networking and Security, Sep 23, 1991
En France, la prevention et la protection contre les risques d'explosion de poussieres dans les m... more En France, la prevention et la protection contre les risques d'explosion de poussieres dans les mines de charbon es t encore fondee sur les principes etablis par J. TAFFANEL [12] au debut du vingtieme siede, comme par exemple la neutralisation des poussieres de charbon par l'admixtion de poussieres incombustibles et l'emploi d'arrets-barrages passifs ä eau. Ces deux procedes servent ä prevenir la propagation des explosions mais il est des situations oü leur utilisation est difficile. En particulier, les galeries en creusement ("cul-de-sac") posent des problemes de securite car ä proximite du front de ces galeries de la poussiere de charbon est produite en permanence. du methane est libere et des sources d'inflammation potentielles sont presentes (comme par exemple, l'impact des pics d'une machine de creusement sur la röche). Des accidents recents ont montre que la probabilite d'explosion, dans cette Situation, n'est pas negligeable. Malheureusement, les moyens de prevention et de protection evoques ci-dessus sont insuffisants pour proteger les culs-de-sac car, en premier lieu, la neutralisation des depöts de poussieres de charbon par l'adjonction d'un materiau pulveruient inerte (procede de "schistification") n'est efficace que si la quantite de poussieres incombustibles deposee sur le poussier de charbon est süffisante [2]
Journal of Loss Prevention in The Process Industries, Sep 1, 2016
The objective of this work-in-progress is to investigate the potentialities but also the limitati... more The objective of this work-in-progress is to investigate the potentialities but also the limitations of traditional risks analysis tools especially in the context of emerging technologies and develop a method facilitating the early detection of scenarios of accidents. This is certainly a challenge particularly for new industrial fields since, in this case, very little or no lesson from past accidents is available. It is believed that such situations cannot be conveniently treated using traditional risk assessment methods (HAZOP, FMEA,...) and typical examples are given. The reason is that those methods rely heavily on past accidents and are therefore "trapped" in them so that they are largely "inductive". In terms of foreseeing the future, the shortcomings of inductive methods are recalled. The possibility to imagine the future with very little clues is then discussed on the ground of theoretical consideration and a way to do so is proposed (abduction, serendipity). Then on the basis of the observation of how the experts work and how discoveries are made, a potential new methodology is outlined.
Etude de la propagation d'une flamme laminaire air-particules d'amidon dans un tube. Dete... more Etude de la propagation d'une flamme laminaire air-particules d'amidon dans un tube. Determination des grandeurs caracteristiques de la flamme. Un des processus possibles de propagation des flammes dans les melanges air-particules d'amidon est celui des ondes de combustion dans les premelanges gazeux
Social Science Research Network, 2022
Social Science Research Network, 2022
The development and subsequent proving of fitness for use of flammable refrigerants for applicati... more The development and subsequent proving of fitness for use of flammable refrigerants for applications that have traditionally used non-flammable working fluids are both complex tasks. The challenges associated with these include: development of acceptable performance characteristics; producing and gaining acceptance of robust safety assessment methodologies, and the need to help facilitate standard setting bodies in developing new working standards. Mexichem has undertaken these activities in several application areas, notably in development of alternatives to R-134a, and has accordingly developed expertise and knowledge of what needs be done. The paper will discuss this process and share some results of development and testing activities connected with 2L refrigerants for a range of applications.
Les explosions sont des phenomenes particulierement complexes a la croisee de disciplines diffici... more Les explosions sont des phenomenes particulierement complexes a la croisee de disciplines difficiles comme la chimie de la combustion, la mecanique des interfaces (les flammes), la mecanique des fluides transitoire et compressible... Le recours a des codes numeriques destines a la resolution des equations fondamentales semble a priori une perspective raisonnable initiee, pour le domaine considere, voici une trentaine d'annee. Il existe aujourd'hui quelques logiciels (de type " CFD ") dont plusieurs sont accessibles (FLUENT, FLACS, AUTOREAGAS,...). Quelques exercices d'intercomparaison ou de confrontation a des experiences " realistes " ont ete realises qui temoignent d'une grande disparite des performances et suggerent que la predictivite n'est pas assuree et que les incertitudes ne sont guere maitrisees. Devant cette situation (qui perdure depuis 20 ans), de grands instituts nationaux, comme HSL en Grande-Bretagne, suggerent que les codes CFD actuels ne seraient pas les plus aptes a l'exercice de prediction. Or il n'est sans doute pas bon a terme de se priver des avantages potentiels qu'offre le vaste domaine de la mecanique des fluides " numerique ". Une tres breve description des outils CFD disponibles pour la simulation des explosions est proposee ainsi qu'un tour d'horizon des resultats de quelques exercices d'intercomparaison issus notamment de travaux tres recents. Quelques enseignements peuvent en etre tires qui suggerent notamment qu'une analyse mathematique et phenomenologique tres precise est requise pour parvenir par exemple a definir des domaines et des procedures d'usage des codes actuels.
Préventique, 2012
F-60550 Verneuil-en-Halatte Jean-Christophe Lecoze Responsable d'études et Recherches à l'INERIS ... more F-60550 Verneuil-en-Halatte Jean-Christophe Lecoze Responsable d'études et Recherches à l'INERIS Direction des Risques Accidentels Parc Technologique ALATA, BP 2 F-60550 Verneuil-en-Halatte « Cela peut paraître paradoxal, mais l'imagination est la perception d'aujourd'hui; nous ne connaissons la situation actuelle que si nous pouvons nous imaginer le possible. »
Journal of Loss Prevention in The Process Industries, Jul 1, 2007
On the basis of a systematic testwork with a number of different dusts, the explosion indices as ... more On the basis of a systematic testwork with a number of different dusts, the explosion indices as determined within the 20l sphere and with the ISO-VDI 1m3 vessel have been compared. The repeatability has been assessed and since some systematic deviations appear a refined physical analysis of the explosion processes is developed. It appears in particular that the cube root
International Journal of Hydrogen Energy, May 1, 2023
The minimum ignition energy (MIE) of hydrogen-air mixture is measured using capacitive spark disc... more The minimum ignition energy (MIE) of hydrogen-air mixture is measured using capacitive spark discharge. First, the effect of humidity on MIE is studied. It is shown that the MIE is approximately constant when the relative humidity increases from 0% to 90% at room temperature. This indicates that humidity has no significant influence on MIE. Next, the effect of spark duration on MIE is studied. The spark duration is increased by connecting a series resistor to the spark circuit. It is shown that the MIE is approximately constant when the spark duration is varied from 5 ns to 1 ms.
Social Science Research Network, 2022
Without a clear understanding of the hazards associated with the failure of CO 2 pipelines, carbo... more Without a clear understanding of the hazards associated with the failure of CO 2 pipelines, carbon capture and storage (CCS) cannot be considered as a viable proposition for tackling the effects of global warming. Given that CO 2 is an asphyxiant at high concentrations, the development of reliable validated pipeline outflow and dispersion models are central to addressing this challenge. This information is pivotal to quantifying all the hazard consequences associated with the failure of CO 2 transportation pipelines, which forms the basis for emergency response planning and determining minimum safe distances to populated areas. This paper presents an overview of the main findings of the recently completed CO2PipeHaz project [1] which focussed on the hazard assessment of CO 2 pipelines to be employed as an integral part of CCS. Funded by the European Commission FP7 Energy programme, the project's main objective was to address this fundamentally important issue.
Some accidents, such as the explosion of the silo in Blaye in August 1997, remind us that explosi... more Some accidents, such as the explosion of the silo in Blaye in August 1997, remind us that explosions of combustible dust can have serious consequences, not only for the industrial installations concerned but also for the environment. The necessity of being able to estimate the effects of an explosion of this type became apparent at the beginning of the 1990s. Owing to the complexity of this subject which involves the mechanical resistance of structures, flame propagation and fluid mechanics, etc., a simulation tool clearly had to be developed. It was in these circumstances that EFFEX was developed. EFFEX is not a software based on the discretization of space but it solves differential equations, each variable of which is considered to be a time function. This is therefore an "integral" type of software code. It is made up of a set of eight modules covering the characterisation of the explosion conditions, the estimation of the mechanical behaviour of the containment and the evaluation of the consequences. Comparison of the results for each of the main modules shows satisfactory consistency with available experimental results. Trials using EFFEX to simulate past accidents, including the transmission and reinforcement of the explosion between subsequent volumes, in order to verify the satisfactory linking of the various modules gave results that were similar to the actual consequences. Several tens of calculation were made so far on silo type of equipments and a synthesis is proposed in addition to a general description of the software.
Processes of the formation of large unconfined clouds following a massive spillage of liquid hydr... more Processes of the formation of large unconfined clouds following a massive spillage of liquid hydrogen on the ground.
Technological Risk Prevention Planning (PPRT) is a French tool for managing land-use planning nea... more Technological Risk Prevention Planning (PPRT) is a French tool for managing land-use planning near upper-tier SEVESO industrial facilities. Its purpose is to protect the population against industrial hazards. Risk limitation measures may include for example window reinforcement for new or existing blast risk exposed buildings. In order to better define technical guidelines for window reinforcement, INERIS developed an innovative experimental device. INERIS has studied window behaviour and has evaluated blast capacity of different kinds of glass panels (monolithic or insulated glasses with or without anti-explosion film, laminated glasses...), mobile frames or window locking or anchorage systems. Results show that all window components have to be considered to improve safety.
This is a repository copy of Application of Turbulence Closures and Thermodynamic Approaches in t... more This is a repository copy of Application of Turbulence Closures and Thermodynamic Approaches in the RANS Modelling of High-Pressure CO2 Releases.
The deployment of a safe, reliable, and financially economical carbon-capture and storage chain r... more The deployment of a safe, reliable, and financially economical carbon-capture and storage chain requires detailed considerations to be made of the hazards of CO2 transportation, and the risks involved in pipeline operation. CO2 poses a number of dangers upon its release, and one major concern is the escalation of a pipeline rupture event due to Joule-Thomson cooling within the vicinity of the expansion, leading to embrittlement and possible running fractures. Capable of releasing several thousand tonnes of high density CO2, such an event could have catastrophic consequences. This paper demonstrates an experimentally validated, numerical approach to the modelling of release scenarios. In addition to the prediction of complex phase behaviour, the approach is capable of quantifying temperatures and pressures for the purpose of fracture propagation modelling. This will further the understanding of hazards associated with CO2 pipeline failure.
Bien des accidents, médiatiques ou non, sont considérés immédiatement après leur réalisation comm... more Bien des accidents, médiatiques ou non, sont considérés immédiatement après leur réalisation comme « imprévisibles » par ceux qu'ils concernent. Pourtant des investigations post-accidentelles font régulièrement surgir des éléments précurseurs dont on n'a pas tenu compte. Ces constats à répétition, peuvent nous conduire à remettre en cause notre capacité d'identification des risques et nous amener à conclure que la seule possibilité qui s'offre à nous, est celle d'un simple recyclage du REX. L'autre alternative qu'explore cette présentation, est de trouver un moyen, avec les méthodes existantes ou avec de nouvelles méthodes, d'identifier a priori de nouveaux risques ou de nouveaux scénarios de réalisation de risques déjà connus.
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Papers by Christophe Proust