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Neutron Noise Calculation using Nodal Expansion Method
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Naser (Supervisor) ; Hosseini, Abolfazl (Co-Advisor)
Abstract
The present M.Sc. thesis consists of two sections including the static calculation and neutron noise calculation in rectangular and hexagonal geometries. The multi-group, two dimensional neutron diffusion equations and corresponding adjoint equations are solved in the static calculation. The spatial discretization of equations is based on Average Current Nodal Expansion Method (ACNEM). Size of nodes is the same size of the fuel assemblies in modeling both of rectangular and hexagonal geometries. The results are benchmarked against the valid results for BIBLIS-2D and IAEA-2D benchmark problems. In the second section, neutron noise calculations are performed for two types of noise sources,...
Neutron noise simulation using ACNEM in the hexagonal geometry
, Article Annals of Nuclear Energy ; Volume 113 , 2018 , Pages 246-255 ; 03064549 (ISSN) ; Vosoughi, N ; Vosoughi, J ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
In the present study, the development of a neutron noise simulator, DYN-ACNEM, using the Average Current Nodal Expansion Method (ACNEM) in 2-G, 2-D hexagonal geometries is reported. In first stage, the static neutron calculation is performed. The neutron/adjoint flux distribution and corresponding eigen-values are calculated using the algorithm developed based on power iteration method by considering the coarse meshes. The results of the static calculation are validated against the well-known IAEA-2D benchmark problem. In the second stage, the dynamic calculation is performed in the frequency domain in which the dimension of the variable space of the noise equations is lower than the time...
Development of SD-HACNEM neutron noise simulator based on high order nodal expansion method for rectangular geometry
, Article Annals of Nuclear Energy ; Volume 162 , 2021 ; 03064549 (ISSN) ; Vosoughi, J ; Vosoughi, N ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
In this study, the SD-HACNEM (Sharif Dynamic - High order Average Current Nodal Expansion Method) neutron noise simulator in two energy groups using a second-order flux expansion method for two-dimensional rectangular X Y-geometry has been developed. In the first step, the calculations were performed for the steady state and results of ACNEM (Average Current Nodal Expansion Method) and HACNEM (High order Average Current Nodal Expansion Method) were examined and compared. To solve the problem, the power iteration algorithm has been used to calculate the distribution of neutron flux and neutron multiplication factor by considering the coarse-mesh (each fuel assembly one node). To validate the...
Study of the effect of frequency in pulse electrodeposition on Au-Ni from cyanide-citrate electrolyte by the aim of design of experiment
, Article Advanced Materials Research, 15 December 2011 through 18 December 2011 ; Volume 410 , December , 2012 , Pages 377-381 ; 10226680 (ISSN) ; 9783037853160 (ISBN) ; Imanieh, I ; Ghorbani, M ; Dolati, A ; Sharif University of Technology
Abstract
The aim of this paper is to study the influence of frequency in pulse electrodeposition, on the current efficiency, Ni content and surface morphology of deposits from a novel cyanide-citrate electrolyte with 20 mM gold as KAu(CN) 2 and 7 mM NiSO 4, with the aim of design of experiment by respond surface method (RSM). Frequency was in the range of 1-200 Hz in constant average current density, temperature, and duty cycle of 7 mA/cm 2, 59 °C and 55% respectively. Composition of the deposits was determined by atomic absorption spectroscopy (AAS). Additionally, deposits were characterized by scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDS). It was shown that from...
Modification of nanostructured anodized aluminum coatings by pulse current mode
, Article Surface and Coatings Technology ; Volume 278 , 2015 , Pages 48-55 ; 02578972 (ISSN) ; Afshar, A ; Sharif University of Technology
Elsevier
2015
Abstract
In this study, the effects of pulse current mode on corrosion resistance and mechanical properties of anodized coatings were explored. Thickness and hardness measurements, polarization and electrochemical impedance spectroscopy were employed to take mechanical and corrosion behaviors of the anodized coatings into consideration. Also, field-emission scanning electron microscopy (FE-SEM) was utilized to characterize the surface morphology of the coatings. It was shown that in short anodizing times, coating thickness is controlled by the heat concentrated on coating. Although at prolonged anodizing times, the coating thickness is affected by average current density. Hardness measurements showed...
Pulsed electrodeposition and characterization of bronze-graphite composite coatings
, Article Surface and Coatings Technology ; Volume 203, Issue 20-21 , 2009 , Pages 3037-3043 ; 02578972 (ISSN) ; Ghorbani, M ; Sharif University of Technology
2009
Abstract
Composite coatings containing self-lubricant particles like graphite, MoS2, PTFE are extensively used to decrease the coefficient of friction of tribo-surfaces. The aim of this study is to investigate the effect of pulse electrodeposition parameters on particle codeposition process and characteristics of bronze-graphite composite coatings electrodeposited from cyanide-stannate bronze electroplating bath. Results showed a slight increase in tin content and a promising increase in hardness of bronze coating by a decrease in duty cycle at constant average current density. Both tin content of the coating and grain refinement seem to participate in hardness enhancement. By increasing the...