Gant S.E.,UK Health and Safety Laboratory |
Narasimhamurthy V.D.,GexCon AS |
Skjold T.,GexCon AS |
Jamois D.,INERIS |
And 2 more authors.
Journal of Loss Prevention in the Process Industries | Year: 2014
A dispersion model validation study is presented for atmospheric releases of dense-phase carbon dioxide (CO2). Predictions from an integral model and two different Computational Fluid Dynamics (CFD) models are compared to data from field-scale experiments conducted by INERIS, as part of the EU-funded CO2PipeHaz project.The experiments studied consist of a 2m3 vessel fitted with a short pipe, from which CO2 was discharged into the atmosphere through either a 6mm or 25mm diameter orifice. Comparisons are made to measured temperatures and concentrations in the multi-phase CO2 jets.The integral dispersion model tested is DNV Phast and the two CFD models are ANSYS-CFX and a research and development version of FLACS, both of which adopt a Lagrangian particle-tracking approach to simulate the sublimating solid CO2 particles in the jet. Source conditions for the CFD models are taken from a sophisticated near-field CFD model developed by the University of Leeds that simulates the multi-phase, compressible flow in the expansion region of the CO2 jet, close to the orifice.Overall, the predicted concentrations from the various models are found to be in reasonable agreement with the measurements, but generally in poorer agreement than has been reported previously for similar dispersion models in other dense-phase CO2 release experiments. The ANSYS-CFX model is shown to be sensitive to the way in which the source conditions are prescribed, while FLACS shows some sensitivity to the solid CO2 particle size. Difficulties in interpreting the results from one of the tests, which featured some time-varying phenomena, are also discussed.The study provides useful insight into the coupling of near- and far-field dispersion models, and the strengths and weaknesses of different modelling approaches. These findings contribute to the assessment of potential hazards presented by Carbon Capture and Storage (CCS) infrastructure. © 2014.
Deschamps L.,Compiègne University of Technology |
Deschamps L.,Center Pierre Guillaumat |
Le Bihan G.,Compiègne University of Technology |
Le Bihan G.,Center Pierre Guillaumat |
And 7 more authors.
Haptics Symposium 2012, HAPTICS 2012 - Proceedings | Year: 2012
For several years, we have been developing a system of perceptual supplementation (Tactos) so as to render spatialized digital information accessible to users with visual deficiencies. After having validated this device in experimental situations and in practical use, we now propose to connect several Tactos systems in a network, so as to allow for access to shared digital spaces via the tactile modality (Intertact). This opening up of previously individual use to collective use makes it possible to conceive digital spaces designed for tactile interaction, by proposing practical, pedagogical and gaming functionalities. This new possibility of tactile interaction opens the way to the production of a technical aid for visually impaired persons with a social dimension. At the same time, the design of shared tactile spaces goes together with a fundamental reflection concerning perceptual interactions. We therefore propose an experimental study in order to provide the necessary steps to characterize the processes of mutual engagement in the interactions. The first results suggest that these processes seem to constitute a mutual dynamics, which is the basis for an active co-construction of meaning. © 2012 IEEE.
Jamois D.,INERIS |
Proust C.,INERIS |
Proust C.,Center Pierre Guillaumat |
Chemical Engineering Transactions | Year: 2014
CCS is seen as a possibility to mitigate the global warming effect. The practical implementation of this technique faces a few challenges like safety issues. It is wondered if a massive spill affecting the pipeline (may be the most vulnerable part of the CCS chain) would not lead to a disaster remembering what happened in Africa about 28 years ago (Eos,2009). In this paper, the experimental techniques used to investigate this specific problem are described and illustrated with some key results extracted from various projects. Innovative techniques were employed to control the mass flowrate, blowdown, near field and far field dispersion in the atmosphere. A 2 m3 spherical vessel able to store up to 1 t of CO2 at a pressure above 70 bar was used. Dense CO2 was allowed to spill out via a 2" pipe. The temperature, CO2 concentration and density field of the outside cloud were monitored using thermocouples and concentration probes via a novel data redaction technique. Among other results, it was in particular shown that when the mass flowrate is large enough, body forces become significant forcing the cloud to stay on the ground. This phenomenon may have played a role during the Nyos Lake accident, explaining perhaps the large number of victims. © Copyright 2014, AIDIC Servizi S.r.l.
Jamois D.,INERIS |
Proust C.,INERIS |
Proust C.,Center Pierre Guillaumat |
Canadian Journal of Chemical Engineering | Year: 2015
CCS (carbon capture and storage) is seen as a possibility to mitigate the global warming effect. The practical implementation of this technique faces a few challenges like safety issues. It is wondered if a massive release affecting the pipeline (may be the most vulnerable part of the CCS chain) would not lead to a disaster remembering what happened in Africa about 28 years ago (about Nyos Lake accident see Eos, 2009). Few experimental observations of large-scale CO2 releases have been made, and the physics and thermochemistry involved are not fully understood, even if considerable progress has been made theoretically.2 In this paper, the experimental techniques used to investigate this specific problem are described and illustrated with some key results extracted from various projects. Innovative techniques were employed to control the mass flowrate, blowdown, nearfield, and farfield dispersion in the atmosphere. A 2m3 spherical vessel able to store up to 1000kg of CO2 at a pressure above 8MPa was used. Dense CO2 was allowed to spill out via a 50mm pipe. The temperature, CO2 concentration, and density field of the outside cloud were monitored using thermocouples and concentration probes. Among other results, it was in particular shown that when the mass flowrate is large enough, body forces become significant forcing the cloud to stay on the ground. © 2014 Canadian Society for Chemical Engineering.
Gres S.,Center Pierre Guillaumat |
Tognini M.,Center Pierre Guillaumat |
Le Cardinal G.,Center Pierre Guillaumat |
Zalila Z.,IntelliTech Microsystems, Inc. |
Gueydan G.,IntelliTech Microsystems, Inc.
Acta Astronautica | Year: 2014
This paper proposes an approach for a complex and innovative project requiring international contributions from different communities of knowledge and expertise. Designing a safe and reliable architecture for a manned mission to Mars or the Asteroids necessitates strong cooperation during the early stages of design to prevent and reduce risks for the astronauts at each step of the mission. The stake during design is to deal with the contradictions, antagonisms and paradoxes of the involved partners for the definition and modeling of a shared project of reference. As we see in our research which analyses the cognitive and social aspects of technological risks in major accidents, in such a project, the complexity of the global organization (during design and use) and the integration of a wide and varie d range of sciences and innovative technologies is likely to increase systemic risks as follows: human and cultural mistakes, potential defaults, failures and accidents. We identify as the main danger antiquated centralized models of organization and the operational limits of interdisciplinarity in the sciences. Beyond this, we can see that we need to take carefully into account human cooperation and the quality of relations between heterogeneous partners. Designing an open, self-learning and reliable exploration system able to self-adapt in dangerous and unforeseen situations implies a collective networked intelligence led by a safe process that organizes interaction between the actors and the aims of the project. Our work, supported by the CNES (French Space Agency), proposes an innovative approach to the coordination of a complex project. © 2014 IAA.
Robert C.,Arts et Metiers ParisTech |
Robert C.,University of Lorraine |
Delamezire A.,University of Lorraine |
Dal Santo P.,Arts et Metiers ParisTech |
Batoz J.L.,Center Pierre Guillaumat
Journal of Materials Processing Technology | Year: 2012
Numerical simulation of the deep drawing process for the manufacture of aeronautical or automotive components should predict with good accuracy the behaviour during the forming operation, taking into account, the material and the process parameters. Existing simulation strategies give good results, however calculation time are long due to the high degree of non-linearities of these problems. The objective of this work is therefore to decrease the calculation time, resulting from the non-linear material behaviour. A new algorithm based on incremental deformation theory (related to Hencky Theory) is presented, in order to compute the plasticity rule in a finite element code (ABAQUS). This algorithm is used to simulate two sheet-metal forming processes: typical stretch forming operation and incremental single point sheet forming. For each case the new algorithm is compared with a classical flow rule plasticity law. In order to have a valid comparison in terms of CPU time, the two material behaviour laws have been implemented in ABAQUS EXPLICIT using the material user function (VUMAT). Good agreement in terms of the stress state and thickness distribution is obtained with the new approach. A significant decrease in CPU time is observed when the major source of non-linearity comes from the material behaviour. © 2011 Elsevier B.V. All rights reserved.