Yazar "Maleki, Bahram R." seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • [ X ]
    Öğe
    Monte Carlo solution of the reflected systems' criticality problems with Anlı-Güngör, Inönü and tetra-anisotropic kernels for both fission and scattered neutrons
    (Indian Acad Sciences, 2024) Maleki, Bahram R.
    Different deterministic solution methods are being used to solve the criticality problem of the reflected systems with different anisotropic behaviours for both fission neutrons and neutrons undergoing scattering. In the present study, the criticality problem is simulated using the developed Monte Carlo algorithm. Different angular distributions, such as In & ouml;n & uuml;, Anl & imath;-G & uuml;ng & ouml;r and tetra-anisotropic kernels are taken into account. For each anisotropic kernel, the sampling method of the direction cosine of either newborn fission neutrons or scattered neutrons is presented by extracting the required probability distribution function (PDF). The simulation starts with an initial guess and following the presented procedure, the criticality thickness of the system is estimated with a certain convergence criterion. Different variance reduction methods, such as implicit capture, Russian-roulette and splitting, are also implemented to get more precise results with a reasonable computational time cost. The validity of the presented method is verified by comparing with the results of different deterministic methods. Finally, using an exact scattering function, the three considered kernels are compared with each other. It is seen that the tetra-anisotropic kernel is the best among the considered kernels.
  • [ X ]
    Öğe
    Simulation of two-point reactor kinetics model of reflected reactors with Newtonian reactivity feedback
    (Pergamon-Elsevier Science Ltd, 2022) Maleki, Bahram R.; Tombakoglu, Mehmet; Goluoglu, Sedat
    In this study, a non-analog dynamic Monte Carlo method, named Point Kinetics Monte Carlo (PKMC), is developed to solve the one-and two-point reactor kinetic equations for a reflected reactor with six group of delayed neutron precursors with Newtonian reactivity feedback. Dynamic weight window technique is implemented to control neutron and precursor population during the simulation. Moreover, the Stochastic differential equations for Two-Point Reactor Kinetics Model (STPRKM) is developed to deter-mine neutron and precursor population as a function of time. Since, the random fluctuations in the pop-ulation dynamics carry very often as much information as the mean value, during the derivation of STPRKM, physical nature of the model problem and inherent probabilistic mechanisms are not altered. Using the developed methods, time dependent transient problems of reflected reactors are studied and mean responses and standard deviations determined by these methods are compared with each other and available deterministic results.(c) 2022 Elsevier Ltd. All rights reserved.
  • [ X ]
    Öğe
    Using the Monte Carlo method to solve the half-space and slab albedo problems with Ino euro nu and Anl?-Gungo euro r strongly anisotropic scattering functions
    (Korean Nuclear Soc, 2023) Maleki, Bahram R.
    Different types of deterministic solution methods were used to solve neutron transport equations cor-responding to half-space and slab albedo problems. In these types of solution methods, in addition to the error of the numerical solutions, the obtained results contain truncation and discretization errors. In the present work, a non-analog Monte Carlo method is provided to simulate the half-space and slab albedo problems with Ino euro nu and Anli-Gungo euro r strongly anisotropic scattering functions. For each scattering function, the sampling method of the direction of the scattered neutrons is presented. The effects of different beams with different angular dependencies and the effects of different scattering parameters on the reflection probability are investigated using the developed Monte Carlo method. The validity of the Monte Carlo method is also confirmed through the comparison with the published data.(c) 2022 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).