The Experts below are selected from a list of 2742 Experts worldwide ranked by ideXlab platform
Hidetoshi Konno - One of the best experts on this subject based on the ideXlab platform.
-
Identification method of stochastic nonlinear dynamics using dynamical phase analysis—application to Forsmark data
Annals of Nuclear Energy, 2004Co-Authors: Fumitoshi Watanabe, Hidetoshi Konno, Shigeru KanemotoAbstract:Abstract We have proposed a new method to identify stochastic nonlinear dynamics of Neutron Fluctuation with “dynamical phase analysis (DPA)”. Availability of the method DPA is demonstrated with the use of Neutron noise data from Forsmark. Also, the features of competing spatial global and regional modes in Forsmark data are discussed physically from the identified stochastic nonlinear model.
-
Effects of spatial higher harmonics and reactivity feedback upon at-power reactor noise patterns
Progress in Nuclear Energy, 2003Co-Authors: Hidetoshi Konno, K. SaitoAbstract:Abstract Effects of spatial higher harmonics and reactivity feedback upon Neutron noise are discussed via the two-group Neutron diffusion and the two-region model of heat transfer by taking into account the space-dependence in the axial direction. Firstly we derive a stochastic non-linear differential equation of Neutron density by contracting the thermo-dynamical variables, fuel and coolant temperature. The spatial and temporal behaviour of reactivity Fluctuation is studied. Secondly the transfer function of inlet coolant to Neutron Fluctuation including feedback is numerically evaluated. Here we discuss the effects of spatial higher harmonics and of reactivity feedback upon the profiles of the transfer function.
-
CML approach to power reactor dynamics (I) - preservation of normality
Annals of Nuclear Energy, 1999Co-Authors: Hidetoshi Konno, Robert Kozma, Masaharu KitamuraAbstract:Abstract An application of coupled map lattice (CML) model for simulating power Fluctuations in nuclear power reactors is presented. (1) Preservation of Gaussianity in the point model is studied in a chaotic force driven Langevin equation in conjunction with the Gaussian-white noise driven Langevin equation. (2) Preservation of Gaussianity is also studied in the space-dependent model with the use of a CML model near the onset of the Hopf bifurcation point. It is shown that the spatial dimensionality decreases as the maximum eigenvalue of the system increases. The result is consistent with the observation of Neutron Fluctuation in a BWR.
Shiyao Lin - One of the best experts on this subject based on the ideXlab platform.
-
Solid scintillator based Neutron Fluctuation measurement on EAST tokamak
Journal of Instrumentation, 2015Co-Authors: Y. B. Zhu, G. Q. Zhong, Shiyao LinAbstract:Microsecond level fast temporal resolved Neutron flux and its Fluctuation measurement system based on three types of solid scintillator detectors has been successfully established on the Experimental Advanced Superconducting Tokamak (EAST) for energetic particle (EP) and magnetohydrodynamics (MHD) instabilities relevant studies. The detector #1, where 50mm thick polyethylene is used for Neutron thermalization, is mostly sensitive to thermal Neutron. The detector #2 and #3 measure fast D-D Neutrons directly with different gamma immunity. Design details together with detector test results with three types of radioisotope sources are presented. The system has been successfully implemented in EAST experiments for Neutron and gamma identification. Typical fast MHD Fluctuation related EAST experimental results from this system is also presented.
N. Morishima - One of the best experts on this subject based on the ideXlab platform.
-
High-frequency structure of space-dependent Neutron Fluctuation spectra in a coupled-core reactor
Annals of Nuclear Energy, 2003Co-Authors: N. MorishimaAbstract:Abstract The space dependence of Neutron Fluctuation spectra in a coupled-core reactor is described in terms of propagation phenomena of Neutron diffusion waves from one core to two space points of observation. Analytical expressions for the spectra are derived for a reference reactor approximately representative of a coupled-core Argonaut-type reactor. Numerical calculations are carried out to illustrate the effect of the difference of two-slab core loading and ring core loading. The results of coherence function calculations provide good agreement with experimental measurements up to and including the frequency at which the real part of the cross spectra for two observation points vanishes.
Masaharu Kitamura - One of the best experts on this subject based on the ideXlab platform.
-
CML approach to power reactor dynamics (I) - preservation of normality
Annals of Nuclear Energy, 1999Co-Authors: Hidetoshi Konno, Robert Kozma, Masaharu KitamuraAbstract:Abstract An application of coupled map lattice (CML) model for simulating power Fluctuations in nuclear power reactors is presented. (1) Preservation of Gaussianity in the point model is studied in a chaotic force driven Langevin equation in conjunction with the Gaussian-white noise driven Langevin equation. (2) Preservation of Gaussianity is also studied in the space-dependent model with the use of a CML model near the onset of the Hopf bifurcation point. It is shown that the spatial dimensionality decreases as the maximum eigenvalue of the system increases. The result is consistent with the observation of Neutron Fluctuation in a BWR.
Y. B. Zhu - One of the best experts on this subject based on the ideXlab platform.
-
Solid scintillator based Neutron Fluctuation measurement on EAST tokamak
Journal of Instrumentation, 2015Co-Authors: Y. B. Zhu, G. Q. Zhong, Shiyao LinAbstract:Microsecond level fast temporal resolved Neutron flux and its Fluctuation measurement system based on three types of solid scintillator detectors has been successfully established on the Experimental Advanced Superconducting Tokamak (EAST) for energetic particle (EP) and magnetohydrodynamics (MHD) instabilities relevant studies. The detector #1, where 50mm thick polyethylene is used for Neutron thermalization, is mostly sensitive to thermal Neutron. The detector #2 and #3 measure fast D-D Neutrons directly with different gamma immunity. Design details together with detector test results with three types of radioisotope sources are presented. The system has been successfully implemented in EAST experiments for Neutron and gamma identification. Typical fast MHD Fluctuation related EAST experimental results from this system is also presented.