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[en] The ET-RR-2 safety analysis evaluation effort included the assessment of the reactor core nuclear design parameters. The present work complements the previous effort of neutronic calculations using NCNSRC computer code packages. This paper is the first in comprehensive neutronic calculation assessment up to the equilibrium core. It deals with evaluation of neutronic calculation submitted during the early phase of the licensing process; namely the proposal to assemble the first critical core, calculation of power peaking factor and determination of detailed energy group flux distribution in the core particularly in the cobalt irradiation position. The neutronic design criteria are examined qualitatively and quantitatively in the present paper
[en] The aim of this work is the evaluation and calculation of the heat generation and temperature rise in local ordinary concrete due to capture of thermal neutrons. The total thermal and reactor thermal neutron fluxes were measured, and the results were used to evaluate the heat generation and temperature rise in ordinary concrete. In addition, the computer code ANISN (VAX version) and neutron multigroup cross-section library EURLiB-4 were used to calculate the total thermal neutron fluxes and the heat generation and hence the temperature rise. The results were displayed in curves to show the distribution of thermal neutron fluxes and the heat generation as well as the temperature rise in the shield thickness. The results showed a good agreement between the measured and calculated values. The results showed also that the heat generation and the temperature rise have their maximum values in the first layers of the shield thickness
[en] A new ET-RR-1 spent fuel storage pool is now under construction on the reactor site at Inshass. In addition, the pool is designed to accommodate spent fuel of MTR type as well. Criticality safety of this pool for the different fuel types has been evaluated as a function of U235 loading. The effect of fuel element separation (rows and columns) on the eigenvalue has been studied. As a conservative assumption, the pool is assumed to be filled with fresh fuel. The eigenvalue considering a realistic degree of fuel burn-up was determined in order to determine the safety margin. The calculations have been carried out using the code packages of the National Center for Nuclear Safety and Radiation Control
[en] The geometries of liquid waste storage tanks are not generally safe against criticality. Normally, this does not cause problems as fissile materials exist in nitric acid solution only as depleted uranium or in insignificant concentration of the originally reprocessed inventory of plutonium. However, if sedimentation of solid particles would occur, the deposited material would cause criticality safety problems. Particularly, non-horizontal installation of the storage tanks would increase the Eigen value. The effect of the storage tank inclination and the presence of transplutonium elements on the criticality safety are investigated using the NCNSRC code packages. The results are compared well with a similar German published results
[en] Highlights: • The (DIPA + AMP + Piperazine) systems are investigated. • A high pressure equilibrium cell is used for solubility measurement. • Piperazine improves H_2S solubility in the (DIPA + AMP) system at high loading. • Electrolyte-NRTL is used for modeling of (H_2S + DIPA + AMP + PZ) systems. - Abstract: Natural gas as a clean source of energy contains several contaminates such as CO_2 and H_2S that is treated through a natural gas purification unit in gas industry. Moreover, for design and construction of gas contactor equipment, it is necessary to obtain experimental values of solubility for H_2S and CO_2 in aqueous amine/alkanolamines. In this work, the solubility of H_2S in the blended aqueous diisopropanolamine (DIPA), 2-amino-2-methyl-1-propanol (AMP) and piperazine (Pz) are measured using a static high pressure apparatus through volumetric method. The values are measured at fixed 45 mass per cent of total amine so that the solubility of H_2S in the present system is investigated under isothermal conditions at T = (313.15, 328.15 and 343.15) K and in the pressure range of (0.1 to 2.1) MPa. The experimental results are presented as the partial pressure of H_2S against acid gas loading (moles H_2S per total moles of amine). Also for modeling the solubility of H_2S in the blended amine/alkanolamines, the Electrolyte-NRTL activity coefficient function is applied to the correlation and prediction of the partial pressure of H_2S versus the acid gas loading. Considering the present results at the given conditions, it is observed that in the low gas loading region, the effect of enhancing Pz on the solubility of H_2S is very low, but at high gas loading the absorption of H_2S is intensified by enhancing mass fraction of Pz in alkanolamine
[en] Correlation between room temperature ultrasonic attenuation coefficient and the most significant structural parameters has been studied in the bioactive silica based glasses, for the first time. The correlation has been carried out in the quaternary SiO_2–Na_2O–CaO–P_2O_5 glass system using the two semi-empirical formulas, which have been presented recently by the author. Changes in the elastic properties, related to the substitution of SiO_2 by alkali Na_2O and alkaline earth CaO oxides, have also been deduced by evaluating the mean atomic volume, packing density, fractal bond connectivity and density of the analogous crystalline structure. Furthermore, values of the theoretical elastic moduli have been calculated on the basis of Makishima-Mackenzie theory and compared with the corresponding observed values. Results show that the correlation between ultrasonic attenuation coefficient and the oxygen density, average atomic ring size, first-order stretching force constant and experimental bulk modulus was achieved at 5 MHz frequency. Values of the theoretically calculated shear modulus are in excellent correlation (C. R. ≻95%) with the corresponding experimental ones. The divergence between the theoretical and experimental values of bulk modulus has been discussed. - Highlights: • Abd El-Moneim model was extended for bioactive glasses. • Ultrasonic attenuation was correlated with structural parameters. • Correlation was carried out in Si–Na–Ca–P glasses. • The model is valid for all investigated glass samples. • Agreement between theoretical and experimental elastic moduli was studied.
[en] The second Egyptian Research Reactor ET-RR-2, is a pool type reactor. A sudden loss of pool water resulting of leaving the core region uncovered. The reactor core is surrounding by a chimney whose water is isolated from the pool water. This accident would lead to significant external dose. A model is developed and is used to calculate the dose maps for key access and traffic areas through the ET-RR-2 reactor. It was found that areas near the reactor platform in direct line of sight of the core have a maximum dose rate. The model developed uses the discrete ordinate method as implemented in the code DOT 3.5. (author)
[en] A microgrid optimal scheduling model is developed in this paper to demonstrate microgrid's capability in offering ancillary services to the utility grid. The application of localized ancillary services is of significant importance to grid operators as the growing proliferation of distributed renewable energy resources, mainly solar generation, is causing major technical challenges in supply-load balance. The proposed microgrid optimal scheduling model coordinates the microgrid net load with the aggregated consumers/prosumers net load in its connected distribution feeder to capture both inter-hour and intra-hour net load variations. In particular, net load variations for three various time resolutions are considered, including hourly ramping, 10-min based load following, and 1-min based frequency regulation. Numerical simulations on a test distribution feeder with one microgrid and several consumers/prosumers indicate the effectiveness of the proposed model and the viability of the microgrid application in supporting grid operation. - Highlights: • Microgrid optimal scheduling for providing ancillary services to the utility grid. • Local management and mitigation of distribution net load variations. • Offering various support services: ramping, load following, frequency regulation. • Proven effectiveness and accuracy in capturing net load variations.