The Experts below are selected from a list of 247374 Experts worldwide ranked by ideXlab platform
A Alamo - One of the best experts on this subject based on the ideXlab platform.
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jules horowitz reactor a high performance Material Testing reactor
Comptes Rendus Physique, 2008Co-Authors: Daniel Iracane, Pascal Chaix, A AlamoAbstract:Abstract The physical modelling of Materials' behaviour under severe conditions is an indispensable element for developing future fission and fusion systems: screening, design, optimisation, processing, licensing, and lifetime assessment of a new generation of structure Materials and fuels, which will withstand high fast neutron flux at high in-service temperatures with the production of elements like helium and hydrogen. JANNUS and other analytical experimental tools are developed for this objective. However, a purely analytical approach is not sufficient: there is a need for flexible experiments integrating higher scales and coupled phenomena and offering high quality measurements; these experiments are performed in Material Testing reactors (MTR). Moreover, complementary representative experiments are usually performed in prototypes or dedicated facilities such as IFMIF for fusion. Only such a consistent set of tools operating on a wide range of scales, can provide an actual prediction capability. A program such as the development of silicon carbide composites (600–1200 °C) illustrates this multiscale strategy. Facing the long term needs of experimental irradiations and the ageing of present MTRs, it was thought necessary to implement a new generation high performance MTR in Europe for supporting existing and future nuclear reactors. The Jules Horowitz Reactor (JHR) project copes with this context. It is funded by an international consortium and will start operation in 2014. JHR will provide improved performances such as high neutron flux ( 10 15 n / cm 2 / s above 0.1 MeV) in representative environments (coolant, pressure, temperature) with online monitoring of experimental parameters (including stress and strain control). Experimental devices designing, such as high dpa and small thermal gradients experiments, is now a key objective requiring a broad collaboration to put together present scientific state of art, end-users requirements and advanced instrumentation. To cite this article: D. Iracane et al., C. R. Physique 9 (2008).
L.g. Rosa - One of the best experts on this subject based on the ideXlab platform.
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temperature control of a solar furnace for Material Testing
International Journal of Systems Science, 2011Co-Authors: Andrade B. Da Costa, João M. Lemos, L.g. RosaAbstract:A solar furnace is a thermodynamic device that concentrates sun radiation in order to achieve high-temperatures at a focus, where a sample of the Material to be tested is located. This article address the problem of designing a control architecture for solar furnaces. It is motivated by the use of a solar furnace as an instrument in Material science research to perform two types of experimental tests. In the first type, samples are tested in high-temperature stress cycles. In these experiments it is important to control the temperature profile. The second test type is characterised by imposing a solar radiation flux profile. On both experiment types there are strong nonlinear effects, a significant degree of parametric uncertainty and disturbances, such as solar radiation fluctuation due to clouds and to sun's apparent movement. Although the actuator (shutter) is much faster than the thermic system, it may destabilise the overall controlled system. The contribution of this article consists in the design of a control architecture for solar furnaces and the application of singular perturbation methods in order to derive conditions in the form of bounds for the speed of actuator dynamics so that the closed-loop system is stable.
Andrade B. Da Costa - One of the best experts on this subject based on the ideXlab platform.
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temperature control of a solar furnace for Material Testing
International Journal of Systems Science, 2011Co-Authors: Andrade B. Da Costa, João M. Lemos, L.g. RosaAbstract:A solar furnace is a thermodynamic device that concentrates sun radiation in order to achieve high-temperatures at a focus, where a sample of the Material to be tested is located. This article address the problem of designing a control architecture for solar furnaces. It is motivated by the use of a solar furnace as an instrument in Material science research to perform two types of experimental tests. In the first type, samples are tested in high-temperature stress cycles. In these experiments it is important to control the temperature profile. The second test type is characterised by imposing a solar radiation flux profile. On both experiment types there are strong nonlinear effects, a significant degree of parametric uncertainty and disturbances, such as solar radiation fluctuation due to clouds and to sun's apparent movement. Although the actuator (shutter) is much faster than the thermic system, it may destabilise the overall controlled system. The contribution of this article consists in the design of a control architecture for solar furnaces and the application of singular perturbation methods in order to derive conditions in the form of bounds for the speed of actuator dynamics so that the closed-loop system is stable.
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an adaptive temperature control law for a solar furnace
Control Engineering Practice, 2009Co-Authors: Andrade B. Da Costa, João M. LemosAbstract:This paper describes the development of an adaptive control law based on the exact feedback linearization and Lyapunov adaptation of the process dynamics applied to a solar furnace. The algorithm resulting from these underlying design principles is approximated in order to relate it with an adaptive PI controller with feedforward. The controller is tested on a 6 kW solar furnace model that represents a plant installed at the Odeillo Processes Materials and Solar Energy Laboratory (Oriental Pyrenees in the South of France). The adaptive features allow to tackle the problems posed by knowledge uncertainty about furnace dynamics. It is concluded that the specifications related to Material Testing are met.
Daniel Iracane - One of the best experts on this subject based on the ideXlab platform.
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jules horowitz reactor a high performance Material Testing reactor
Comptes Rendus Physique, 2008Co-Authors: Daniel Iracane, Pascal Chaix, A AlamoAbstract:Abstract The physical modelling of Materials' behaviour under severe conditions is an indispensable element for developing future fission and fusion systems: screening, design, optimisation, processing, licensing, and lifetime assessment of a new generation of structure Materials and fuels, which will withstand high fast neutron flux at high in-service temperatures with the production of elements like helium and hydrogen. JANNUS and other analytical experimental tools are developed for this objective. However, a purely analytical approach is not sufficient: there is a need for flexible experiments integrating higher scales and coupled phenomena and offering high quality measurements; these experiments are performed in Material Testing reactors (MTR). Moreover, complementary representative experiments are usually performed in prototypes or dedicated facilities such as IFMIF for fusion. Only such a consistent set of tools operating on a wide range of scales, can provide an actual prediction capability. A program such as the development of silicon carbide composites (600–1200 °C) illustrates this multiscale strategy. Facing the long term needs of experimental irradiations and the ageing of present MTRs, it was thought necessary to implement a new generation high performance MTR in Europe for supporting existing and future nuclear reactors. The Jules Horowitz Reactor (JHR) project copes with this context. It is funded by an international consortium and will start operation in 2014. JHR will provide improved performances such as high neutron flux ( 10 15 n / cm 2 / s above 0.1 MeV) in representative environments (coolant, pressure, temperature) with online monitoring of experimental parameters (including stress and strain control). Experimental devices designing, such as high dpa and small thermal gradients experiments, is now a key objective requiring a broad collaboration to put together present scientific state of art, end-users requirements and advanced instrumentation. To cite this article: D. Iracane et al., C. R. Physique 9 (2008).
João M. Lemos - One of the best experts on this subject based on the ideXlab platform.
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temperature control of a solar furnace for Material Testing
International Journal of Systems Science, 2011Co-Authors: Andrade B. Da Costa, João M. Lemos, L.g. RosaAbstract:A solar furnace is a thermodynamic device that concentrates sun radiation in order to achieve high-temperatures at a focus, where a sample of the Material to be tested is located. This article address the problem of designing a control architecture for solar furnaces. It is motivated by the use of a solar furnace as an instrument in Material science research to perform two types of experimental tests. In the first type, samples are tested in high-temperature stress cycles. In these experiments it is important to control the temperature profile. The second test type is characterised by imposing a solar radiation flux profile. On both experiment types there are strong nonlinear effects, a significant degree of parametric uncertainty and disturbances, such as solar radiation fluctuation due to clouds and to sun's apparent movement. Although the actuator (shutter) is much faster than the thermic system, it may destabilise the overall controlled system. The contribution of this article consists in the design of a control architecture for solar furnaces and the application of singular perturbation methods in order to derive conditions in the form of bounds for the speed of actuator dynamics so that the closed-loop system is stable.
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an adaptive temperature control law for a solar furnace
Control Engineering Practice, 2009Co-Authors: Andrade B. Da Costa, João M. LemosAbstract:This paper describes the development of an adaptive control law based on the exact feedback linearization and Lyapunov adaptation of the process dynamics applied to a solar furnace. The algorithm resulting from these underlying design principles is approximated in order to relate it with an adaptive PI controller with feedforward. The controller is tested on a 6 kW solar furnace model that represents a plant installed at the Odeillo Processes Materials and Solar Energy Laboratory (Oriental Pyrenees in the South of France). The adaptive features allow to tackle the problems posed by knowledge uncertainty about furnace dynamics. It is concluded that the specifications related to Material Testing are met.