Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le co... more Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le comportement des ecoulements gaz-solide concentres dans les lits fluidises circulants (LFC), en mettant l'accent sur le comportement des clusters ou des ensembles de particules. Cette modelisation a ete effectuee en utilisant l'approche eulerienne pour les deux phases gazeuse et solide. Un modele de fermeture pour la phase solide a ete propose en definissant une energie cinetique liee aux fluctuations macroscopiques. L'equation de transport de cette energie, comprend une viscosite apparente pour la phase solide, differente de la viscosite produite due aux collisions. En vue de determiner cette viscosite, un modele empirique, base sur le concept de longueur de melange de la phase solide a ete utilisee. La longueur de melange a ete estimee par la mesure des cofluctuations de vitesses axiales et des profils de vitesses moyennes axiales dans la zone etablie d'une maquette LFC. Le modele a ete evalue en effectuant quelques exemples d'applications numeriques sur des geometries bidimensionnelles, correspondants a differentes zones et echelles d'ecoulement dans les systemes LFC. Il a permis de decrire quelques aspects caracteristiques du comportement de la phase solide. Un degre significatif de segregation entre les phases a ete observe, avec des concentrations plus importantes au niveau des parois. Le modele doit etre complete par des fermetures pour les correlations entre les vitesses de gaz et de solide, l'anisotropie des fluctuations de vitesse, et les variations de la longueur de melange de la phase solide.
Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le co... more Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le comportement des ecoulements gaz-solide concentres dans les lits fluidises circulants (LFC), en mettant l'accent sur le comportement des clusters ou des ensembles de particules. Cette modelisation a ete effectuee en utilisant l'approche eulerienne pour les deux phases gazeuse et solide. Un modele de fermeture pour la phase solide a ete propose en definissant une energie cinetique liee aux fluctuations macroscopiques. L'equation de transport de cette energie, comprend une viscosite apparente pour la phase solide, differente de la viscosite produite due aux collisions. En vue de determiner cette viscosite, un modele empirique, base sur le concept de longueur de melange de la phase solide a ete utilisee. La longueur de melange a ete estimee par la mesure des cofluctuations de vitesses axiales et des profils de vitesses moyennes axiales dans la zone etablie d'une maquette LFC. ...
Journal of Water, Sanitation and Hygiene for Development, 2020
There is a strong need for transformative sanitation systems in the areas of the world where open... more There is a strong need for transformative sanitation systems in the areas of the world where open defecation habits and/or inadequate sewage treatment methods and facilities exist. This paper describes an innovative thermally efficient solid waste treatment process as a basis for an off-the-grid, non-sewered toilet in order to address this need. Human feces are combusted in a continuous-cyclic manner using two stages of smoldering and catalytic oxidation. It has been shown that thermal coupling of the two stages creates a self-sustained reactor that can combust wet fecal material containing up to 3.2 parts water to 1 part dry matter – equivalent of water content in healthy human feces – without the need for external heating, known as the ultimate challenge in direct combustion of human feces. Furthermore, it has been shown that air flow rate can be reliably used as a controlling mechanism for fecal destruction rate which means the same reactor could be operated for various and varyi...
The present invention relates to a method for the production of ultra fine spherical metal powder... more The present invention relates to a method for the production of ultra fine spherical metal powders by chemical gas deposition and decomposition technique, the powder is a metal-containing process gas comprises a metal-carbonyl is propelled towards the heated reactor. As the gas flow and toward the conventional lower part receiving the gas flow towards the opposite top, the theoretical plug-in implementation than the adjacent approximate value of the flow velocity profile is, reduction to the conventional technology is required, or a relatively narrow particle size the distribution is caused.
Verfahren zur Herstellung eines offenporigen Metallschaumkorpers, mit einer Nickel-Basislegierung... more Verfahren zur Herstellung eines offenporigen Metallschaumkorpers, mit einer Nickel-Basislegierung, bei dem ein offenporiger Basisschaumkorper aus Nickel oder einer Nickel-Basislegierung mit einem flussigen Binder beschichtet, anschliesend ein in fester Phase vorliegendes Gemisch, das mit einer pulverformigen Nickel-Basislegierung und einer organischen Komponente gebildet ist, wobei die Phasenumwandlungstemperatur der organischen Komponente von ihrer festen Phase in die flussige Phase mindestens 30°C betragt, bei einer Temperatur unterhalb der jeweiligen Phasenumwandlungstemperatur auf mit dem Binder beschichtete Oberflachen des Basisschaumkorpers aufgebracht und mittels einer Warmebehandlung der Binder und die organische Komponente ausgetrieben, sowie ein Teil der Pulverpartikel gesintert und ein weiterer Teil der Pulverpartikel uber Sinterbrucken mit der Oberflache des Basisschaumkorpers stoffschlussig verbunden werden.
Process comprising the steps of: (a) providing a metal foam body having a pore size between 100 a... more Process comprising the steps of: (a) providing a metal foam body having a pore size between 100 and 5000 microns, a thickness of the strut in the range of 5 to 60 microns, a bulk density in the range of 300 to 1200 kg / m3, a geometric surface in the range of 100 to 20000 m2 / m3 and a porosity in the range 0.50 to 0.95 and comprising a first metallic material, wherein the first metallic material contains at least a metal selected from the group consisting of Ni, Fe, Cr, Co, Cu, Ag, Au, Pt and Pd; (B) applying a second metallic material different from the first metallic material on a surface of the metal foam body, wherein the surface of the metal foam body (a) is coated with an organic binder and a powder of the second metal material and wherein aluminum is used as the second metallic material; (C) forming a skin of alloy metal foam body obtained in step (b) by alloying the first metal material and second metal material, where the formation of an alloy of the first metal material a...
L'invention a trait a un procede de production de poudres metalliques spheriques extra-fines ... more L'invention a trait a un procede de production de poudres metalliques spheriques extra-fines par des techniques de dissolution et de depot chimique en phase vapeur, comprenant des carbonyles metalliques, le metal contenant un gaz de traitement etant propulse vers le haut par un reacteur chauffe. En employant un flux de gaz montant, par opposition au flux de gaz descendant conventionnel, on obtient une meilleure approximation des profils de vitesse d'ecoulement sub-laminaire theorique, ce qui entraine une distribution de particules de taille de preference plus etroite, limitant ou reduisant le besoin de techniques de classification ulterieures.
A process for preparing an open-pored metal foam body with a nickel base alloy, in which an open-... more A process for preparing an open-pored metal foam body with a nickel base alloy, in which an open-pore base foam body made of nickel or a nickel-based alloy coated with a liquid binder, then a present in a solid phase mixture that is formed with a powdery nickel base alloy and an organic component, wherein the phase transition temperature of the organic component from its solid phase to the liquid phase is at least 30 ° C at at a temperature below the respective phase transition temperature applied with the binder-coated surfaces of the base foam body and expelled by means of a heat treatment of the binder and the organic component, as well as sintered part of the powder particles and a further part of the powder particles are firmly bonded via sintering bridges with the surface of the base foam body.
Apparatus for Separation contained in exhaust gases of internal combustion engines particles in t... more Apparatus for Separation contained in exhaust gases of internal combustion engines particles in the exhaust stream of an internal combustion engine is guided through a filter medium and are received in the filter medium particles from the exhaust gas stream and retained, wherein the filter medium (1) from a metal open-pore foam having at least two layers (1.1, 1.2, 1.3) is formed and thereby, the thickness, the mean porosity and / or the mean pore size of the layers (1.1, 1.2, 1.3) in the direction of flow through the filter medium (1) decreases, characterized in that the free cross section of an inlet channel (2) in the direction of flow of the particle-containing exhaust gas is itself formed demagnifying and / or decreases the porosity and / or the mean pore size of the filter medium (1) at least in one of the layers (1.1, 1.2, 1.3) contained in the inflow direction of the particle exhaust gas in an intake passage (2), wherein the inflow direction flowed through in parallel to the...
Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le co... more Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le comportement des ecoulements gaz-solide concentres dans les lits fluidises circulants (LFC), en mettant l'accent sur le comportement des clusters ou des ensembles de particules. Cette modelisation a ete effectuee en utilisant l'approche eulerienne pour les deux phases gazeuse et solide. Un modele de fermeture pour la phase solide a ete propose en definissant une energie cinetique liee aux fluctuations macroscopiques. L'equation de transport de cette energie, comprend une viscosite apparente pour la phase solide, differente de la viscosite produite due aux collisions. En vue de determiner cette viscosite, un modele empirique, base sur le concept de longueur de melange de la phase solide a ete utilisee. La longueur de melange a ete estimee par la mesure des cofluctuations de vitesses axiales et des profils de vitesses moyennes axiales dans la zone etablie d'une maquette LFC. Le modele a ete evalue en effectuant quelques exemples d'applications numeriques sur des geometries bidimensionnelles, correspondants a differentes zones et echelles d'ecoulement dans les systemes LFC. Il a permis de decrire quelques aspects caracteristiques du comportement de la phase solide. Un degre significatif de segregation entre les phases a ete observe, avec des concentrations plus importantes au niveau des parois. Le modele doit etre complete par des fermetures pour les correlations entre les vitesses de gaz et de solide, l'anisotropie des fluctuations de vitesse, et les variations de la longueur de melange de la phase solide.
Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le co... more Ce travail a ete consacre au developpement d'un modele theorique dans le but de decrire le comportement des ecoulements gaz-solide concentres dans les lits fluidises circulants (LFC), en mettant l'accent sur le comportement des clusters ou des ensembles de particules. Cette modelisation a ete effectuee en utilisant l'approche eulerienne pour les deux phases gazeuse et solide. Un modele de fermeture pour la phase solide a ete propose en definissant une energie cinetique liee aux fluctuations macroscopiques. L'equation de transport de cette energie, comprend une viscosite apparente pour la phase solide, differente de la viscosite produite due aux collisions. En vue de determiner cette viscosite, un modele empirique, base sur le concept de longueur de melange de la phase solide a ete utilisee. La longueur de melange a ete estimee par la mesure des cofluctuations de vitesses axiales et des profils de vitesses moyennes axiales dans la zone etablie d'une maquette LFC. ...
Journal of Water, Sanitation and Hygiene for Development, 2020
There is a strong need for transformative sanitation systems in the areas of the world where open... more There is a strong need for transformative sanitation systems in the areas of the world where open defecation habits and/or inadequate sewage treatment methods and facilities exist. This paper describes an innovative thermally efficient solid waste treatment process as a basis for an off-the-grid, non-sewered toilet in order to address this need. Human feces are combusted in a continuous-cyclic manner using two stages of smoldering and catalytic oxidation. It has been shown that thermal coupling of the two stages creates a self-sustained reactor that can combust wet fecal material containing up to 3.2 parts water to 1 part dry matter – equivalent of water content in healthy human feces – without the need for external heating, known as the ultimate challenge in direct combustion of human feces. Furthermore, it has been shown that air flow rate can be reliably used as a controlling mechanism for fecal destruction rate which means the same reactor could be operated for various and varyi...
The present invention relates to a method for the production of ultra fine spherical metal powder... more The present invention relates to a method for the production of ultra fine spherical metal powders by chemical gas deposition and decomposition technique, the powder is a metal-containing process gas comprises a metal-carbonyl is propelled towards the heated reactor. As the gas flow and toward the conventional lower part receiving the gas flow towards the opposite top, the theoretical plug-in implementation than the adjacent approximate value of the flow velocity profile is, reduction to the conventional technology is required, or a relatively narrow particle size the distribution is caused.
Verfahren zur Herstellung eines offenporigen Metallschaumkorpers, mit einer Nickel-Basislegierung... more Verfahren zur Herstellung eines offenporigen Metallschaumkorpers, mit einer Nickel-Basislegierung, bei dem ein offenporiger Basisschaumkorper aus Nickel oder einer Nickel-Basislegierung mit einem flussigen Binder beschichtet, anschliesend ein in fester Phase vorliegendes Gemisch, das mit einer pulverformigen Nickel-Basislegierung und einer organischen Komponente gebildet ist, wobei die Phasenumwandlungstemperatur der organischen Komponente von ihrer festen Phase in die flussige Phase mindestens 30°C betragt, bei einer Temperatur unterhalb der jeweiligen Phasenumwandlungstemperatur auf mit dem Binder beschichtete Oberflachen des Basisschaumkorpers aufgebracht und mittels einer Warmebehandlung der Binder und die organische Komponente ausgetrieben, sowie ein Teil der Pulverpartikel gesintert und ein weiterer Teil der Pulverpartikel uber Sinterbrucken mit der Oberflache des Basisschaumkorpers stoffschlussig verbunden werden.
Process comprising the steps of: (a) providing a metal foam body having a pore size between 100 a... more Process comprising the steps of: (a) providing a metal foam body having a pore size between 100 and 5000 microns, a thickness of the strut in the range of 5 to 60 microns, a bulk density in the range of 300 to 1200 kg / m3, a geometric surface in the range of 100 to 20000 m2 / m3 and a porosity in the range 0.50 to 0.95 and comprising a first metallic material, wherein the first metallic material contains at least a metal selected from the group consisting of Ni, Fe, Cr, Co, Cu, Ag, Au, Pt and Pd; (B) applying a second metallic material different from the first metallic material on a surface of the metal foam body, wherein the surface of the metal foam body (a) is coated with an organic binder and a powder of the second metal material and wherein aluminum is used as the second metallic material; (C) forming a skin of alloy metal foam body obtained in step (b) by alloying the first metal material and second metal material, where the formation of an alloy of the first metal material a...
L'invention a trait a un procede de production de poudres metalliques spheriques extra-fines ... more L'invention a trait a un procede de production de poudres metalliques spheriques extra-fines par des techniques de dissolution et de depot chimique en phase vapeur, comprenant des carbonyles metalliques, le metal contenant un gaz de traitement etant propulse vers le haut par un reacteur chauffe. En employant un flux de gaz montant, par opposition au flux de gaz descendant conventionnel, on obtient une meilleure approximation des profils de vitesse d'ecoulement sub-laminaire theorique, ce qui entraine une distribution de particules de taille de preference plus etroite, limitant ou reduisant le besoin de techniques de classification ulterieures.
A process for preparing an open-pored metal foam body with a nickel base alloy, in which an open-... more A process for preparing an open-pored metal foam body with a nickel base alloy, in which an open-pore base foam body made of nickel or a nickel-based alloy coated with a liquid binder, then a present in a solid phase mixture that is formed with a powdery nickel base alloy and an organic component, wherein the phase transition temperature of the organic component from its solid phase to the liquid phase is at least 30 ° C at at a temperature below the respective phase transition temperature applied with the binder-coated surfaces of the base foam body and expelled by means of a heat treatment of the binder and the organic component, as well as sintered part of the powder particles and a further part of the powder particles are firmly bonded via sintering bridges with the surface of the base foam body.
Apparatus for Separation contained in exhaust gases of internal combustion engines particles in t... more Apparatus for Separation contained in exhaust gases of internal combustion engines particles in the exhaust stream of an internal combustion engine is guided through a filter medium and are received in the filter medium particles from the exhaust gas stream and retained, wherein the filter medium (1) from a metal open-pore foam having at least two layers (1.1, 1.2, 1.3) is formed and thereby, the thickness, the mean porosity and / or the mean pore size of the layers (1.1, 1.2, 1.3) in the direction of flow through the filter medium (1) decreases, characterized in that the free cross section of an inlet channel (2) in the direction of flow of the particle-containing exhaust gas is itself formed demagnifying and / or decreases the porosity and / or the mean pore size of the filter medium (1) at least in one of the layers (1.1, 1.2, 1.3) contained in the inflow direction of the particle exhaust gas in an intake passage (2), wherein the inflow direction flowed through in parallel to the...
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