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International audience ; The present social context imposes effective reductions of transport greenhouse gases and pollutant emissions. To answer to this demand, car manufacturers adopted technologies such as downsizing, turbocharging, intense in-cylinder aerodynamics and diluted combustion process. In this context, to master mixture ignition is crucial to ensure an efficient heat release. To get to a clearer knowledge about the physics holding early stages of premixed mixture combustion, the PRISME institute in the framework of the French government research project ANR MACDOC generated a consistent experimental database to study ignition and spherical flame propagation processes in a constant volume vessel in laminar and turbulent environment. This allows to have a detailed description of the flame dynamics of an air / isooctane mixture depending on thermochemical properties of the mixture and nature of the diluent (O2, H2O, CO2 and synthetic stoichiometric Exhaust Gas Recirculation (EGR)), as well as on turbulent intensity and ignition energy. A system simulation model based on the Coherent Flame Model (CFM) approach was then setup at IFP Energies nouvelles (IFPEN) accounting for the influence of the flame stretch, through the integration of a non-linear formulation of the mixture Markstein number, and the flame wrinkling due to turbulence. The model allowed to have a deeper insight in the interpretation of experiments and to dissociate the interacting phenomena holding the combustion process. This modeling improving seems to be a necessary step to model next generation Spark Ignition engines operating under steady and transient conditions.

International audience ; The present social context imposes effective reductions of transport greenhouse gases and pollutant emissions. To answer to this demand, car manufacturers adopted technologies such as downsizing, turbocharging, intense in-cylinder aerodynamics and diluted combustion process. In this context, to master mixture ignition is crucial to ensure an efficient heat release. To get to a clearer knowledge about the physics holding early stages of premixed mixture combustion, the PRISME institute in the framework of the French government research project ANR MACDOC generated a consistent experimental database to study ignition and spherical flame propagation processes in a constant volume vessel in laminar and turbulent environment. This allows to have a detailed description of the flame dynamics of an air / isooctane mixture depending on thermochemical properties of the mixture and nature of the diluent (O2, H2O, CO2 and synthetic stoichiometric Exhaust Gas Recirculation (EGR)), as well as on turbulent intensity and ignition energy. A system simulation model based on the Coherent Flame Model (CFM) approach was then setup at IFP Energies nouvelles (IFPEN) accounting for the influence of the flame stretch, through the integration of a non-linear formulation of the mixture Markstein number, and the flame wrinkling due to turbulence. The model allowed to have a deeper insight in the interpretation of experiments and to dissociate the interacting phenomena holding the combustion process. This modeling improving seems to be a necessary step to model next generation Spark Ignition engines operating under steady and transient conditions.

International audience ; The present social context imposes effective reductions of transport greenhouse gases and pollutant emissions. To answer to this demand, car manufacturers adopted technologies such as downsizing, turbocharging, intense in-cylinder aerodynamics and diluted combustion process. In this context, to master mixture ignition is crucial to ensure an efficient heat release. To get to a clearer knowledge about the physics holding early stages of premixed mixture combustion, the PRISME institute in the framework of the French government research project ANR MACDOC generated a consistent experimental database to study ignition and spherical flame propagation processes in a constant volume vessel in laminar and turbulent environment. This allows to have a detailed description of the flame dynamics of an air / isooctane mixture depending on thermochemical properties of the mixture and nature of the diluent (O2, H2O, CO2 and synthetic stoichiometric Exhaust Gas Recirculation (EGR)), as well as on turbulent intensity and ignition energy. A system simulation model based on the Coherent Flame Model (CFM) approach was then setup at IFP Energies nouvelles (IFPEN) accounting for the influence of the flame stretch, through the integration of a non-linear formulation of the mixture Markstein number, and the flame wrinkling due to turbulence. The model allowed to have a deeper insight in the interpretation of experiments and to dissociate the interacting phenomena holding the combustion process. This modeling improving seems to be a necessary step to model next generation Spark Ignition engines operating under steady and transient conditions.

Ce numéro d'Innovations Agronomiques rassemble les présentations du colloque `` Ville à haute intensité écologique : la place du végétal '' qui s'est tenu à Angers le 30 septembre 2015. ; International audience ; Many changes in our society (urban planning, life style, economic crisis…) impact on the ornamental plant chain. Moreover, political awareness on the risk of chemicals used in plant protection (including the recent adoption of the Labbé Law) imposes a change in people behaviour and management of these plants. The whole chain of the ornamental plant breeding and distribution has been aware for many years of the change and the need to develop new breeding programs for ornamental plants. These changes are in progress but take time; for example, the breeding of new varieties of rose is a long, challenging and labour process. In rose breeding, disease resistance is today one of the main traits but combined with other major traits of ornamental plants such as flower colour, fragrance and architecture. To help the breeders, new research projects have been developed in collaboration with private companies in order to understand the genetic determinism of disease resistances and to develop new tools for resistance characterisation. ; Les évolutions rapides de notre société (urbanisme, rythme de vie, crise économique,…) impactent le secteur de production des plantes ornementales. De plus, des prises de conscience importantes de la société sur les risques sanitaires de l'utilisation de pesticides de synthèse (avec notamment l'adoption de la loi Labbé) imposent des changements de comportement et de gestion de ces plantes. L'ensemble de la filière a bien conscience, et ce depuis plusieurs années, de ces évolutions et de la nécessité de changer les schémas de sélection des plantes ornementales. Ces changements sont en cours mais les pas de temps sont à prendre en compte ; la création de nouvelles variétés de rosiers reste un processus long et laborieux. Dans le schéma de sélection du rosier, la résistance aux ...

Ce numéro d'Innovations Agronomiques rassemble les présentations du colloque « Ville à haute intensité écologique : la place du végétal » qui s'est tenu à Angers le 30 septembre 2015. ; Many changes in our society (urban planning, life style, economic crisis…) impact on the ornamental plant chain. Moreover, political awareness on the risk of chemicals used in plant protection (including the recent adoption of the Labbé Law) imposes a change in people behaviour and management of these plants. The whole chain of the ornamental plant breeding and distribution has been aware for many years of the change and the need to develop new breeding programs for ornamental plants. These changes are in progress but take time; for example, the breeding of new varieties of rose is a long, challenging and labour process. In rose breeding, disease resistance is today one of the main traits but combined with other major traits of ornamental plants such as flower colour, fragrance and architecture. To help the breeders, new research projects have been developed in collaboration with private companies in order to understand the genetic determinism of disease resistances and to develop new tools for resistance characterisation. ; Les évolutions rapides de notre société (urbanisme, rythme de vie, crise économique,…) impactent le secteur de production des plantes ornementales. De plus, des prises de conscience importantes de la société sur les risques sanitaires de l'utilisation de pesticides de synthèse (avec notamment l'adoption de la loi Labbé) imposent des changements de comportement et de gestion de ces plantes. L'ensemble de la filière a bien conscience, et ce depuis plusieurs années, de ces évolutions et de la nécessité de changer les schémas de sélection des plantes ornementales. Ces changements sont en cours mais les pas de temps sont à prendre en compte ; la création de nouvelles variétés de rosiers reste un processus long et laborieux. Dans le schéma de sélection du rosier, la résistance aux pathogènes est devenue un critère ...

Ce numéro d'Innovations Agronomiques rassemble les présentations du colloque « Ville à haute intensité écologique : la place du végétal » qui s'est tenu à Angers le 30 septembre 2015. ; Many changes in our society (urban planning, life style, economic crisis…) impact on the ornamental plant chain. Moreover, political awareness on the risk of chemicals used in plant protection (including the recent adoption of the Labbé Law) imposes a change in people behaviour and management of these plants. The whole chain of the ornamental plant breeding and distribution has been aware for many years of the change and the need to develop new breeding programs for ornamental plants. These changes are in progress but take time; for example, the breeding of new varieties of rose is a long, challenging and labour process. In rose breeding, disease resistance is today one of the main traits but combined with other major traits of ornamental plants such as flower colour, fragrance and architecture. To help the breeders, new research projects have been developed in collaboration with private companies in order to understand the genetic determinism of disease resistances and to develop new tools for resistance characterisation. ; Les évolutions rapides de notre société (urbanisme, rythme de vie, crise économique,…) impactent le secteur de production des plantes ornementales. De plus, des prises de conscience importantes de la société sur les risques sanitaires de l'utilisation de pesticides de synthèse (avec notamment l'adoption de la loi Labbé) imposent des changements de comportement et de gestion de ces plantes. L'ensemble de la filière a bien conscience, et ce depuis plusieurs années, de ces évolutions et de la nécessité de changer les schémas de sélection des plantes ornementales. Ces changements sont en cours mais les pas de temps sont à prendre en compte ; la création de nouvelles variétés de rosiers reste un processus long et laborieux. Dans le schéma de sélection du rosier, la résistance aux pathogènes est devenue un critère principal tout en maintenant les autres critères ornementaux (couleur de la fleur, parfum, forme), ce qui pose le problème du cumul de caractères dans les nouvelles variétés. Pour accompagner ces schémas de sélection, des programmes de recherche sont développés en partenariat avec les obtenteurs et producteurs pour mieux comprendre le déterminisme génétique des résistances et pour développer des outils de caractérisation de ces résistances.

Les évolutions rapides de notre société (urbanisme, rythme de vie, crise économique,…) impactent le secteur de production des plantes ornementales. De plus, des prises de conscience importantes de la société sur les risques sanitaires de l'utilisation de pesticides de synthèse (avec notamment l'adoption de la loi Labbé) imposent des changements de comportement et de gestion de ces plantes. L'ensemble de la filière a bien conscience, et ce depuis plusieurs années, de ces évolutions et de la nécessité de changer les schémas de sélection des plantes ornementales. Ces changements sont en cours mais les pas de temps sont à prendre en compte ; la création de nouvelles variétés de rosiers reste un processus long et laborieux. Dans le schéma de sélection du rosier, la résistance aux pathogènes est devenue un critère principal tout en maintenant les autres critères ornementaux (couleur de la fleur, parfum, forme), ce qui pose le problème du cumul de caractères dans les nouvelles variétés. Pour accompagner ces schémas de sélection, des programmes de recherche sont développés en partenariat avec les obtenteurs et producteurs pour mieux comprendre le déterminisme génétique des résistances et pour développer des outils de caractérisation de ces résistances. ; Many changes in our society (urban planning, life style, economic crisis…) impact on the ornamental plant chain. Moreover, political awareness on the risk of chemicals used in plant protection (including the recent adoption of the Labbé Law) imposes a change in people behaviour and management of these plants. The whole chain of the ornamental plant breeding and distribution has been aware for many years of the change and the need to develop new breeding programs for ornamental plants. These changes are in progress but take time; for example, the breeding of new varieties of rose is a long, challenging and labour process. In rose breeding, disease resistance is today one of the main traits but combined with other major traits of ornamental plants such as flower colour, fragrance and architecture. To help the breeders, new research projects have been developed in collaboration with private companies in order to understand the genetic determinism of disease resistances and to develop new tools for resistance characterisation.

Ce numéro d'Innovations Agronomiques rassemble les présentations du colloque « Ville à haute intensité écologique : la place du végétal » qui s'est tenu à Angers le 30 septembre 2015. ; Many changes in our society (urban planning, life style, economic crisis…) impact on the ornamental plant chain. Moreover, political awareness on the risk of chemicals used in plant protection (including the recent adoption of the Labbé Law) imposes a change in people behaviour and management of these plants. The whole chain of the ornamental plant breeding and distribution has been aware for many years of the change and the need to develop new breeding programs for ornamental plants. These changes are in progress but take time; for example, the breeding of new varieties of rose is a long, challenging and labour process. In rose breeding, disease resistance is today one of the main traits but combined with other major traits of ornamental plants such as flower colour, fragrance and architecture. To help the breeders, new research projects have been developed in collaboration with private companies in order to understand the genetic determinism of disease resistances and to develop new tools for resistance characterisation. ; Les évolutions rapides de notre société (urbanisme, rythme de vie, crise économique,…) impactent le secteur de production des plantes ornementales. De plus, des prises de conscience importantes de la société sur les risques sanitaires de l'utilisation de pesticides de synthèse (avec notamment l'adoption de la loi Labbé) imposent des changements de comportement et de gestion de ces plantes. L'ensemble de la filière a bien conscience, et ce depuis plusieurs années, de ces évolutions et de la nécessité de changer les schémas de sélection des plantes ornementales. Ces changements sont en cours mais les pas de temps sont à prendre en compte ; la création de nouvelles variétés de rosiers reste un processus long et laborieux. Dans le schéma de sélection du rosier, la résistance aux pathogènes est devenue un critère ...

International audience ; Due to its strong impact on health, particulate matter is increasingly regulated by government emission standards for vehicles. As one of the sources of particulate matter is the soot produced by internal combustion engines, it remains a challenge to improve advanced combustion modes to reduce it. There is still, however, some lack of understanding about the formation and oxidation processes of soot, especially in "realistic" conditions, such as for example at high temperature and pressure conditions with or without the presence of exhaust gases. The objective of this study is to investigate soot formation in the case of n-Dodecane spray flames at conventional Diesel engine conditions generated in the New One Shot Engine by using diffused back-illumination extinction with different CO2 and water vapour contents. It was found that CO2 addition reduces the soot mass fraction if its volumetric concentration in ambient mixtures is at least 4.5% while 1% of water is sufficient to significantly reduce the soot mass fraction. The impact of the ambient mixture obtained in ECN spray A pre-burn vessels was also investigated to assess the accuracy against soot measurements available in the literature.

International audience ; Due to its strong impact on health, particulate matter is increasingly regulated by government emission standards for vehicles. As one of the sources of particulate matter is the soot produced by internal combustion engines, it remains a challenge to improve advanced combustion modes to reduce it. There is still, however, some lack of understanding about the formation and oxidation processes of soot, especially in "realistic" conditions, such as for example at high temperature and pressure conditions with or without the presence of exhaust gases. The objective of this study is to investigate soot formation in the case of n-Dodecane spray flames at conventional Diesel engine conditions generated in the New One Shot Engine by using diffused back-illumination extinction with different CO2 and water vapour contents. It was found that CO2 addition reduces the soot mass fraction if its volumetric concentration in ambient mixtures is at least 4.5% while 1% of water is sufficient to significantly reduce the soot mass fraction. The impact of the ambient mixture obtained in ECN spray A pre-burn vessels was also investigated to assess the accuracy against soot measurements available in the literature.