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Data assimilation applied to combustion

Mélanie C. Rochoux, Bénédicte Cuenot, Sophie Ricci, Arnaud Trouvé, Blaise Delmotte, Sébastien Massart, Roberto Paoli, Ronan Paugam
2013 Comptes rendus. Mecanique  
Data assimilation is a sophisticated technique, yet not available in combustion, that combines measurements to model simulation and account for uncertainties in order to improve the numerical prediction of a system. In the context of gas turbines, data assimilation may be used for example to improve the prediction of flame ignition and propagation by a smart analysis of images and measurements. A first illustration of data assimilation is given in a simple case, where synthetic time-evolving
more » ... itions of the flame front are assimilated to calibrate parameters of a premixed flame model. Its successful application in the context of natural fire propagation assesses the predictive capacity of the technique and the resulting higher fidelity in the data-driven simulations. To cite this article: M.C. Rochoux et al., C. R. Mecanique 333 (2011). Résumé Assimilation de données en combustion. L'assimilation de données, encore inappliquée en combustion, combine mesures et simulations en tenant compte des incertitudes afin d'améliorer la prévision numérique d'un système. Dans le contexte des turbinesà gaz, l'assimilation de données peutêtre utilisée par exemple pour améliorer l'estimation de l'allumage et de la propagation de la flamme, grâceà une exploitation plus poussée de données telles que des images ou des mesures ponctuelles. Une première illustration de l'assimilation de données est présentée pour la prédiction de la propagation d'un front de flamme dans un cas test simple. Dans cet exemple, les positions du front de flamme au cours du temps sont assimilées pour caler les paramètres d'un modèle de flamme prémélangée. La capacité de prédiction des simulations obtenues par assimilation de données est finalement démontrée dans un cas réel de propagation de feux naturels. Pour citer cet article : M. C. Rochoux et al., C. R. Mecanique 333 (2011).
doi:10.1016/j.crme.2012.10.011 fatcat:rzrhsmogsfalvafln6rqamuyji

Space-based observational constraints for 1-D fire smoke plume-rise models

Maria Val Martin, Ralph A. Kahn, Jennifer A. Logan, Ronan Paugam, Martin Wooster, Charles Ichoku
2012 Journal of Geophysical Research  
We use a space-based plume height climatology derived from 3 observations made by the Multi-angle Imaging SpectroRadiometer (MISR) 4 instrument aboard the NASA Terra satellite to evaluate the ability of a plume-5 rise model currently embedded in several atmospheric chemical transport mod-6 els (CTMs) to produce accurate smoke injection heights. We initialize the 7 plume-rise model with assimilated meteorological fields from the NASA God-8 dard Earth Observing System and estimated fuel moisture
more » ... ontent at the lo-9 cation and time of the MISR measurements. Fire properties that drive the 10 plume-rise model are difficult to estimate and we test the model with four 11 estimates for active fire area and four for total heat flux, obtained using em-12 pirical data and Moderate Resolution Imaging Spectroradiometer (MODIS) 13 fire radiative power (FRP) thermal anomalies available for each MISR plume. 14 We show that the model is not able to reproduce the plume heights observed 15 by MISR over the range of conditions studied (maximum r 2 obtained in all 16 configurations is 0.3). The model also fails to determine which plumes are 17 in the free troposphere (according to MISR), key information needed for at-18 mospheric models to simulate properly smoke dispersion. We conclude that 19 embedding a plume-rise model using currently available fire constraints in 20 large-scale atmospheric studies remains a difficult proposition. However, we 21 demonstrate the degree to which the fire dynamical heat flux (related to ac-22 tive fire area and sensible heat flux), and atmospheric stability structure in-23 fluence plume rise, although other factors less well constrained (e.g., entrain-24 ment) may also be significant. Using atmospheric stability conditions, MODIS FRP, and MISR plume heights, we offer some constraints on the main phys-26 ical factors that drive smoke plume rise. We find that smoke plumes reach-27 ing high altitudes are characterized by higher FRP and weaker atmospheric 28 stability conditions than those at low altitude, which tend to remain con-29 fined below the BL, consistent with earlier results. We propose two simpli-30 fied parameterizations for computing injection heights for fires in CTMs and 31 discuss current challenges to representing plume injection heights in large 32 scale atmospheric models. representing injection heights in models is a difficult task, complicated by the sparseness 43 of plume height measurements to validate the calculated values. The space-based plume 44 height climatology derived from observations made by the Multi-angle Imaging SpectroRa-45 diometer (MISR) instrument aboard the NASA Terra satellite provides a unique dataset 46 for extensive validation of injection heights. We use these data to evaluate a one dimen-47 sional (1-D) plume-rise parameterization currently used to simulate injection heights in 48 CTMs, and to investigate the main physical factors that determine smoke plume rise. 49
doi:10.1029/2012jd018370 fatcat:huby46civjag5acumsfzw5baby

Direct estimation of Byram's fire intensity from infrared remote sensing imagery

Joshua M. Johnston, Martin J. Wooster, Ronan Paugam, Xianli Wang, Timothy J. Lynham, Lynn M. Johnston
2017 International journal of wildland fire  
Paugam et al. 2013, Fig. 2a). When applied to high-resolution imagery, Eqn 7 is rasterised by 98 , B rad I is 99 100 101 Table 5 ) 5 .  ...  measurements, the brightness temperature 191 (BT) threshold indicating the time of arrival was increased from the assumed 650 K (Paugam et al. 2013) 192 to 773 K.  ... 
doi:10.1071/wf16178 fatcat:d6at74ljx5dmlgmkcx5kzyfawu

Flame-Front Rate of Spread Estimates for Moderate Scale Experimental Fires Are Strongly Influenced by Measurement Approach

Joshua Johnston, Melanie Wheatley, Martin Wooster, Ronan Paugam, G. Davies, Kaitlin DeBoer
2018 Fire  
We identify one of the thermal infrared imaging methods (described in Paugam et al. 2013), as the most appropriate for providing rate and direction of spread at these scales of measurement.  ...  Infrared Paugam et al. 2013 Based Methods Paugam et al. (2013) identified flame fronts in infrared imagery using an IR BT threshold of 650 K, whereas our revised version used a threshold of 773 K (as in  ...  Figure 7 . 7 Linear regression results comparing mean thermocouple grid rate of spread (RoS) values to the (a) Infrared Grid Array (b) Paugam et al. (2013) and (c) Paugam et al. (2013) 773 K methods RoS  ... 
doi:10.3390/fire1010016 fatcat:xkv3zhc6nrespdju2rd7qxjq7u

The Global Fire Atlas of individual fire size, duration, speed, and direction

Niels Andela, Douglas C. Morton, Louis Giglio, Ronan Paugam, Yang Chen, Stijn Hantson, Guido R. van der Werf, James T. Randerson
2018 Earth System Dynamics Discussions  
<p><strong>Abstract.</strong> Natural and human-ignited fires affect all major biomes, altering ecosystem structure, biogeochemical cycles, and atmospheric composition. Satellite observations provide global data on spatiotemporal patterns of biomass burning and evidence for rapid changes in global fire activity in response to land management and climate. Satellite imagery also provides detailed information on the daily or subdaily position of fires that can be used to understand the dynamics of
more » ... individual fires. The Global Fire Atlas is a new global dataset that tracks the dynamics of individual fires to determine the timing and location of ignitions and fire size, duration, daily expansion, fire line length, speed, and direction of spread. Here we present the underlying methodology and Global Fire Atlas results for 2003&amp;ndash;2016 derived from daily moderate resolution (500<span class="thinspace"></span>m) Collection 6 MCD64A1 burned area data. The algorithm identified 13.3 million individual fires over the study period, and estimated fire perimeters were in good agreement with independent data for the continental United States. A small number of large fires dominated sparsely populated arid and boreal ecosystems, while burned area in agricultural and other human-dominated landscapes was driven by high ignition densities that resulted in numerous smaller fires. Long-duration fires in the boreal regions and natural landscapes in the humid tropics suggest that fire-season length exerts a strong control on fire size and total burned area in these areas. In arid ecosystems with low fuel densities, high fire spread rates resulted in large, short-duration fires that quickly consumed available fuels. Importantly, multi-day fires contributed the majority of burned area in all biomass burning regions. A first analysis of the largest, longest, and fastest fires that occurred around the world revealed coherent regional patterns of extreme fires driven by large-scale climate forcing. Global Fire Atlas data are publicly available through <a href=" http://www.globalfiredata.org/"target="_blank">www.globalfiredata.org/</a> and <a href="https://doi.org/10.3334/ORNLDAAC/1642" target="_blank">https://doi.org/10.3334/ORNLDAAC/1642</a>, and individual fire information and summary data products provide new information for benchmarking fire models within ecosystem and Earth system models, understanding vegetation-fire feedbacks, improving global emissions estimates, and characterizing the changing role of fire in the Earth system.</p>
doi:10.5194/essd-2018-89 fatcat:6bjlwp5xurhxhfhc3fldsf7rt4

The Global Fire Atlas of individual fire size, duration, speed and direction

Niels Andela, Douglas C. Morton, Louis Giglio, Ronan Paugam, Yang Chen, Stijn Hantson, Guido R. van der Werf, James T. Randerson
2019 Earth System Science Data  
<p><strong>Abstract.</strong> Natural and human-ignited fires affect all major biomes, altering ecosystem structure, biogeochemical cycles and atmospheric composition. Satellite observations provide global data on spatiotemporal patterns of biomass burning and evidence for the rapid changes in global fire activity in response to land management and climate. Satellite imagery also provides detailed information on the daily or sub-daily position of fires that can be used to understand the
more » ... of individual fires. The Global Fire Atlas is a new global dataset that tracks the dynamics of individual fires to determine the timing and location of ignitions, fire size and duration, and daily expansion, fire line length, speed, and direction of spread. Here, we present the underlying methodology and Global Fire Atlas results for 2003–2016 derived from daily moderate-resolution (500&amp;thinsp;m) Collection 6 MCD64A1 burned-area data. The algorithm identified 13.3 million individual fires over the study period, and estimated fire perimeters were in good agreement with independent data for the continental United States. A small number of large fires dominated sparsely populated arid and boreal ecosystems, while burned area in agricultural and other human-dominated landscapes was driven by high ignition densities that resulted in numerous smaller fires. Long-duration fires in boreal regions and natural landscapes in the humid tropics suggest that fire season length exerts a strong control on fire size and total burned area in these areas. In arid ecosystems with low fuel densities, high fire spread rates resulted in large, short-duration fires that quickly consumed available fuels. Importantly, multiday fires contributed the majority of burned area in all biomass burning regions. A first analysis of the largest, longest and fastest fires that occurred around the world revealed coherent regional patterns of extreme fires driven by large-scale climate forcing. Global Fire Atlas data are publicly available through <span class="uri">http://www.globalfiredata.org</span> (last access: 9 August 2018) and <a href="https://doi.org/10.3334/ORNLDAAC/1642">https://doi.org/10.3334/ORNLDAAC/1642</a>, and individual fire information and summary data products provide new information for benchmarking fire models within ecosystem and Earth system models, understanding vegetation–fire feedbacks, improving global emissions estimates, and characterizing the changing role of fire in the Earth system.</p>
doi:10.5194/essd-11-529-2019 fatcat:wkcif6bsjrd7ng5w2mdccstb4e

Orthorectification of Helicopter-Borne High Resolution Experimental Burn Observation from Infra Red Handheld Imagers

Ronan Paugam, Martin J. Wooster, William E. Mell, Mélanie C. Rochoux, Jean-Baptiste Filippi, Gernot Rücker, Olaf Frauenberger, Eckehard Lorenz, Wilfrid Schroeder, Bruce Main, Navashni Govender
2021 Remote Sensing  
To pursue the development and validation of coupled fire-atmosphere models, the wildland fire modeling community needs validation data sets with scenarios where fire-induced winds influence fire front behavior, and with high temporal and spatial resolution. Helicopter-borne infrared thermal cameras have the potential to monitor landscape-scale wildland fires at a high resolution during experimental burns. To extract valuable information from those observations, three-step image processing is
more » ... uired: (a) Orthorectification to warp raw images on a fixed coordinate system grid, (b) segmentation to delineate the fire front location out of the orthorectified images, and (c) computation of fire behavior metrics such as the rate of spread from the time-evolving fire front location. This work is dedicated to the first orthorectification step, and presents a series of algorithms that are designed to process handheld helicopter-borne thermal images collected during savannah experimental burns. The novelty in the approach lies on its recursive design, which does not require the presence of fixed ground control points, hence relaxing the constraint on field of view coverage and helping the acquisition of high-frequency observations. For four burns ranging from four to eight hectares, long-wave and mid infra red images were collected at 1 and 3 Hz, respectively, and orthorectified at a high spatial resolution (<1 m) with an absolute accuracy estimated to be lower than 4 m. Subsequent computation of fire radiative power is discussed with comparison to concurrent space-borne measurements.
doi:10.3390/rs13234913 fatcat:zvefyewm5jgi3f75d7mptqn6ti

Open fires in Greenland in summer 2017: transport, deposition and radiative effects of BC, OC and BrC emissions

Nikolaos Evangeliou, Arve Kylling, Sabine Eckhardt, Viktor Myroniuk, Kerstin Stebel, Ronan Paugam, Sergiy Zibtsev, Andreas Stohl
2019 Atmospheric Chemistry and Physics  
Injection altitudes, assumptions on biomass consumption and emissions factors Injection heights into the atmosphere of the emitted smoke were simulated with version 2 of the plume rise model (PRM; Paugam  ... 
doi:10.5194/acp-19-1393-2019 fatcat:gxh6um53nfcd7cabhfx6x3hpay

Two global data sets of daily fire emission injection heights since 2003

Samuel Rémy, Andreas Veira, Ronan Paugam, Mikhail Sofiev, Johannes W. Kaiser, Franco Marenco, Sharon P. Burton, Angela Benedetti, Richard J. Engelen, Richard Ferrare, Jonathan W. Hair
2017 Atmospheric Chemistry and Physics  
., 2006; Paugam et al., 2016) .  ...  The main changes of PRMv2, compared to PRMv0, are described in Paugam et al. (2015) .  ... 
doi:10.5194/acp-17-2921-2017 fatcat:ky7telgaajfgxhdqddewbdy64m

Open fires in Greenland: an unusual event and its impact on the albedo of the Greenland Ice Sheet

Nikolaos Evangeliou, Arve Kylling, Sabine Eckhardt, Viktor Myroniuk, Kerstin Stebel, Ronan Paugam, Sergiy Zibtsev, Andreas Stohl
2018 Atmospheric Chemistry and Physics Discussions  
altitudes, assumptions on biomass consumption and emissions 119 factors 120 Injection heights into the atmosphere of the emitted smoke were simulated with version 121 2 of the Plume Rise Model (PRM) (Paugam  ... 
doi:10.5194/acp-2018-94 fatcat:lbsqhkyaczdvtaqyl7e6zpa4zq

Source attribution using FLEXPART and carbon monoxide emission inventories: SOFT-IO version 1.0

Bastien Sauvage, Alain Fontaine, Sabine Eckhardt, Antoine Auby, Damien Boulanger, Hervé Petetin, Ronan Paugam, Gilles Athier, Jean-Marc Cousin, Sabine Darras, Philippe Nédélec, Andreas Stohl (+3 others)
2017 Atmospheric Chemistry and Physics  
As in the MIXED method, GFAS v1.2 is using the plume model PRMV2 from Paugam et al. (2015) , but here the model is run globally for every assimilated GFAS-FRP pixel.  ...  Pyro-convection plume dynamics are often associated with small-scale processes that are not represented in global meteorological data and emission inventories (Paugam et al., 2016) .  ... 
doi:10.5194/acp-17-15271-2017 fatcat:2flurbhvcjgcfjrq3r3bgsykii

Source attribution using FLEXPART and carbon monoxide emission inventories: SOFT-IO version 1.0

Bastien Sauvage, Alain Fontaine, Sabine Eckhardt, Antoine Auby, Damien Boulanger, Hervé Petetin, Ronan Paugam, Gilles Athier, Jean-Marc Cousin, Sabine Darras, Philippe Nédélec, Andreas Stohl (+3 others)
2017 Atmospheric Chemistry and Physics Discussions  
table computed with the 238 plume rise model PRMv2 presented in Paugam et al. (2015).  ...  Pyro-convection plume dynamics are often associated with small-scale processes that 229 are not represented in global meteorological data and emission inventories (Paugam et al 2016) .  ... 
doi:10.5194/acp-2017-653 fatcat:atvnq4bbc5ew7i2w4qeuni26xu

Fire behaviour and smoke modelling: model improvement and measurement needs for next-generation smoke research and forecasting systems

Yongqiang Liu, Adam Kochanski, Kirk R. Baker, William Mell, Rodman Linn, Ronan Paugam, Jan Mandel, Aime Fournier, Mary Ann Jenkins, Scott Goodrick, Gary Achtemeier, Fengjun Zhao (+12 others)
2019 International journal of wildland fire  
There is an urgent need for next-generation smoke research and forecasting (SRF) systems to meet the challenges of the growing air quality, health, and safety concerns associated with wildland fire emissions. This review paper presents simulations and experiments of hypothetical prescribed burns with a suite of selected fire behavior and smoke models and identifies major issues for model improvement and the most critical observational needs. The results are used to understand the new and
more » ... d capability required for the next-generation SRF systems and to support the design of the Fire and Smoke Model Evaluation Experiment (FASMEE) and other field campaigns. The next-generation SRF systems should have more coupling of fire, smoke, and atmospheric processes to better simulate and forecast vertical smoke distributions and multiple sub-plumes, dynamical and high-resolution fire processes, and local and regional smoke chemistry during day and night. The development of the coupling capability requires comprehensive and spatially and temporally integrated measurements across the various disciplines to characterize flame and energy structure (e.g., individual cells, vertical heat profile and the height of well mixing flaming gases), smoke structure (vertical distributions and multiple sub-plumes), ambient air processes (smoke eddy, entrainment and radiative effects of smoke aerosols), fire emissions (for different fuel types and combustion conditions from flaming to residual smoldering), as well as night-time processes (smoke drainage and super-fog formation).
doi:10.1071/wf18204 pmid:32632343 pmcid:PMC7336523 fatcat:lf44z474jred5mk2janjl5ubi4

Fire detection from hyperspectral data using neural network approach

Alessandro Piscini, Stefania Amici, Christopher M. U. Neale, Antonino Maltese
2015 Remote Sensing for Agriculture, Ecosystems, and Hydrology XVII  
ACKNOWLEDGMENTS We are grateful to Professor Martin Wooster and Ronan Paugam, to provide the hyperspectral data and information related to the flights.  ... 
doi:10.1117/12.2194911 fatcat:33cwz2zn7jbdjf5dfmkf65jrbu

Bio-bibliographie de Dominique Schnapper

2009 Revue européenne des sciences sociales  
Directions de thèses Direction de thèses soutenues : Riva Kastoryano (1984), Jeane Brody (1986), Abdelwahed Allouche (1987), Serge Paugam (1988), Ronan Serrier (1990), Yeza Boulhabel Villac (1991), Ali  ...  II. 231 – « Intégration et exclusion dans les sociétés modernes », dans Serge Paugam (dir.), L’Exclusion.  ... 
doi:10.4000/ress.273 fatcat:to6je4ga3jflfjxp5qui774xlu
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