Algerian Journal of Engineering and Technology (AJET)
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Modeling of nuclear reactor core for power control simulation with temperature feedback and xenon concentration effect
Get PDFModeling nuclear reactor cores stands as an essential initial step in nuclear technology research and development. The reactor core, serving as the primary thermal energy source in nuclear power plants (NPPs), plays a pivotal role. Such reactor core modeling serves various objectives, including core power control and load-following operations within NPPs. In this study, the pressurized water reactor (PWR) core was modeled using the point reactor method, a technique widely applied in conjunction with multiple reactor core power control strategies during load-following operations. Employing a proportional-integral-derivative (PID) controller, load-following scenarios tailored to grid load maneuvers were implemented in the developed reactor core model. The study also delved into the effects of temperature feedback and xenon. The analysis of simulation results revealed only a very small deviation in power between the desired and actual reactor core power. A substantial movement of the control rods effectively countered the notable impact of xenon on reactor power. Regarding temperature feedback, its contribution to the core total réactivity with a negative reactivity was confirmed. This study utilized the Python language for both the development of the nuclear reactor model and the creation of algorithms required for power control during load-following mode. Typically, similar endeavors with distinct objectives are conducted using MATLAB SIMULINK
Study of the elaboration of U3O8 by the Modified Direct Denitration process (MDD)
Get PDFIn the nuclear industry, uranium trioxide (UO3) is considered an intermediate in the preparation of uranium metal or uranium dioxide (UO2), which are the two most widely used nuclear fuels. Several processes have been described for transforming solutions of uranyl nitrate UO2(NO3)2 into uranium trioxide. Among these processes, Modified Direct Denitration (MDD) has been implemented to prepare Uranium trioxide with high reactivity. This process consists of adding ammonium nitrate to a pure uranyl nitrate solution to form the double salt (NH4)2UO2(NO3)4.2H2O which decomposes by calcination to produce a UO3 powder. The objective of this work is to study, first, the thermal decomposition of double salt (NH4)2UO2(NO3)4.2H2O in nitrogen atmosphere by thermogravimetry in order to determine the formation temperatures of the different phases and second, the determination of the optimal parameters (time and temperature) to prepare stable triuranium octoxide (U3O8) using muffle furnace. As results, the MDD product obtained is an orange colored and free flowing UO3 powder, having a surface area in the target range [5-12 m2/g]. In addition, by calcination of UO3 powder at 650°C for one hour, U3O8 oxide is obtained. The identification of the latter by the O/U ratio gave a value of 2.65, which is in the range [2.6-2.66]. This suggests that the oxide produced under these conditions is β-U3O8
Aerodynamic analysis of a small-scale drone propeller using the blade element momentum method
Get PDFIn this study, the aerodynamic performance of a small-scale drone propeller (Tmotor28 propeller) in axial flight has been analyzed using the Blade Element Momentum Theory (BEMT). Which is a powerful tool to model the aerodynamic interaction between the rotor/propeller and the fluid flow. The aim of this paper is to propose a BEMT model for the Unmanned Aerial Vehicle (UAV). An open-source tool known as pyBEMT (Python programming language) has been used to calculate the aerodynamic performance of the propeller. The XFoil, which is based on the panel-vortex methods, has been used to find the lift and drag coefficients (CD and CL) of the propeller airfoils. The numerical results have been validated with experimental results. Good agreements have been found. This study introduces a straightforward and powerful calculation method for predicting and optimizing the aerodynamic performance of drones
A Brief review of features of copper indium disulphide (CuInS2) nanomaterial for quantum dot solar cell
Get PDFCopper indium disulphide CuInS2 (CIS) is found to be an interesting nanomaterial belong to group I-III-V for quantum dot solar cell (QDSCs) application due to low toxicity, multiple exciton generation effect, high light absorption in the visible spectral range, appropriate band gap that coordinate well with the solar spectrum, unusual radiation tolerance, noticeable defect tolerance and low cost. Properties of this material that makes it important for use in quantum dot solar cell is also discussed in this paper. This paper summarizes the research going on in the field of synthesis of CuInS2 nanomaterials reported by different authors across the globe. Optical and photovoltaic properties of reviewed CIS QDSCs is also highlighted in this paper
Sol-gel synthesis of ZnO nanoparticles for optmized photocatalytic degradation of Eriochrome Black T under UV irradiation
Get PDFIn this work, zinc oxide (ZnO) nanoparticles was synthesized by sol-gel method and characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), energy dispersive spectroscopy (EDS) and ultraviolet-visible (UV-Vis) spectrophotometry. The XRD analysis of the as synthesized catalyst revealed a hexagonal wurtzite structure. The average particle size and band gap values were 24.67nm and 3.28eV respectively. The peak observed at 452cm-1 corresponds to Zn-O stretching vibrational band. The effect of operating paramers such as initial concentration of eriochrome black-T (EBT), concentration of catalyst and pH of the solution was optimized using box-benhken design (BBD) and response surface methodology (RSM). The optimum photodegradation efficiency of 96.59% was obtained at 15.00mg of EBT concentration, 0.40g catalyst concentration and initial pH of 9.00. The degradation model was statistically remarkable with p < 0.0001% in which the EBT initial concentration and catalyst concentration were the most significant variables influencing the degradation of EBT over ZnO photocatalyst under UV irradiation
An overview of the relative neutron activation analysis performed in the NAA Laboratory of the CRND using NUR reactor
Get PDFNeutron activation analysis is a highly sensitive method for multi-elemental analysis, primarily focusing on the induced radioactivity in atomic nuclei rather than the inherent chemical and physical properties of samples. This approach requires exposing the sample to neutron irradiation, typically conducted within a nuclear reactor. One of the most successful applications of Instrumental Neutron Activation Analysis (INAA) in the vicinity of the NUR reactor pertains to its use in environmental studies. It facilitates the monitoring of the distribution of trace elements (TEs) and the attribution of emission sources by analyzing samples from diverse environmental sources, including soil, air, and bioaccumulative plants collected from various locations near Algiers, Algeria. Since 2010, our laboratory has actively engaged in proficiency tests with WEPAL/IAEA, which has been instrumental in advancing and refining the methods of Neutron Activation Analysis (NAA) employed in this domain. The outcomes derived from these environmental investigations substantiate the presence of more than 30 trace elements. Comparing the enrichment factors (FEs) reveals the contribution of anthropogenic pollution, such as vehicles emitting Sb, Se, and Zn, brickyards releasing As, Co, Cr, Fe, Na, Se, Sc, Ta, and Tb, as well as soil resuspension leading to the release of Br and Zn. Additionally, our laboratory has conducted further studies in the realm of biology using the relative approach of NAA. The primary objective has been to harness the potential of NAA for early diagnosis in cases of cancer and chronic diseases. Consequently, we've examined the trace element composition in the whole blood of both healthy individuals and those afflicted by illnesses. We achieved this by subjecting lyophilized blood samples from adult subjects to simultaneous irradiation alongside an A13-IAEA blood standard. The elemental concentrations were subsequently calculated by measuring gamma rays using a gamma spectrometer. We simultaneously determines the concentrations of ten elements: Rb, Fe, Zn, Na, K, Br, Se, Sr, As and Sc
Measurement of radioactivity levels in powdered milk consumed in Algeria and estimation of annual effective doses
Get PDFThe monitoring of radioactivity in food, especially in milk, has become a top priority in many countries. This paper presents the activity concentrations of 40K, 226Ra, 232Th and 137Cs radionuclides measured in twenty-two samples of the powdered milk available in the Algerian market, sourced from different regions worldwide. The measurements were conducted using an HPGe detector by employing the gamma spectrometry method. The results show that the specific activity of 40K, 226Ra and 232Th in infant powdered milk samples varied from (133.57±1.75 to 195.95±2.56 Bq/kg), (1.35±0.03 to 2.70±0.07 Bq/kg) and (1.34±0.03 to 1.63±0.06 Bq/kg), respectively. In adult powdered milk samples, the activity concentration of 40K, 226Ra 232Th and 137Cs were varied from (110.52±1.49 to 687.89±8.94 Bq/kg), (1.38±0.04 to 2.59±0.10 Bq/kg), (1.25±0.03 to 2.63±0.09 Bq/kg) and (3.60±0.07 to 7.78±0.11 Bq/kg), respectively. The obtained results were subsequently compared with data from various studies conducted globally. The estimated annual ingestion dose resulting from the consumption of powdered milk was found to be 583.80 µSv/y infants (≤ 1y), and 56.85 µSv/y for adults (≥ 17y). These values indicate that powdered milk in Algeria does not have a significant radiological impact on the population, as they are below the dose limit recommended by the World Health Organization
Numerical simulation of time-fractional Navier-Stokes equation in cylindrical coordinates for an unsteady one-dimensional motion of a viscous fluid flow in a given tube
Get PDFThis paper proposed and applied a three-step computational algorithm to solve the time-fractional Navier-Stokes equation (FNS) in a given cylindrical coordinates for one-way unstable flow motion. The Caputo definition of fraction order was obtained using the Riemann Liouville fractional integral operator, which was coded with the MAPLE18 software command and applied to simulate the different fractional values presented in 2D and 3D surface graphs for understanding better the operation of fractional Navier-Stokes equations over time in cylindrical coordinates. We considered different test cases to show the proposed algorithm's efficiency, robustness, and feasibility, which ultimately reduces the computational time and ease of implementation for the simulation of the fractional order of the fractional Navier-Stokes equation considered
Gamma spectrometry technique application to the 60Co sorption onto IRN-77 resin from radioactive wastewater: Equilibrium, Kinetic and Thermodynamic investigations
Get PDFThe performance of synthetic ion exchange resin IRN-77 have been studied in this work in order to use it as an adsorbent to remove radioactive isotope 60Co from nuclear wastewater by the sorption process, using the gamma spectrometry technique. The resin simple was identified using SEM and FTIR infrared spectrometry. The gamma radiation acquisition emitted from the fixed radioactive 60Co onto IRN-77 solid samples was carried out using the gamma spectrometry chain, equipped with an HPGe semi-conductor detector with high-resolution. Various factors were considered for the sorption process study such as 60Co concentration, contact time and temperature. The maximum adsorption capacity of the IRN-77 samples was determined by studying the adsorption isotherms; Kinetics models including thermodynamics were also studied and investigated. The experimental results showed that the adsorption reaction was adjustable to the pseudo-first-order and the Langmuir model was found to describe best the experimental results by obtaining a very important maximum adsorption quantity of 10.620 µCi of 60Co per 1 gram of IRN-77 adsorbent. A dimensionless separation factor RL was used to judge the favorable adsorption. The adsorption capacity of 60Co ions onto IRN-77 particles increased with the increasing of temperature. The values of the thermodynamic parameters have shown that the 60Co ions adsorption process was endothermic and favored at high temperatures with a positive value of the enthalpy ∆H° of 23,54 kJ/mol. The free energy’s values ∆G◦ are positive over the whole temperature range. The specific activities of the fixed 60Co radionuclide allow evaluating the solid samples IRN-77 resin's sorption capacity
A Multi-objectives regression, optimization and risk assessment of profitability indicators of the simulation of mini Liquefied Petroleum Gas (LPG) dispensing unit
No full textIn this study, simulation of a mini Liquefied Petroleum Gas (LPG) dispensing unit was conducted using ASPEN HYSYS and the operation of both compressor and pump were validated theoretically. The effect of the economic parameters (Total Annual Sales (TAS), Total Production Cost (TPC), Fixed Capital Investment (FCI) and interest rate (r)) on the behaviour of three profitability indicators (Net Present Value (NPV), Return on investment (ROI) and Internal Rate of Return (IRR)) were modelled and optimized using Box Behnken Design (BBD). The uncertainty of the developed models was determined using Oracle Crystal Ball (ORB). The optimum economic parameters, TAS of ₦48,830,600, FCI of ₦37,422,000, TPC of ₦35, 053,000 and r of 5.4% predicted optimum profitability indicators are ROI of 34.6%, NPV of ₦98,993,580.25 and IRR of 34.15% for 15 years’ investment plan. An interaction of the economic parameters showed that for NPV to be positive, TAS value should be greater than ₦42.5 million and the TPC should be less or equal to ₦36 million. The profitability analysis suggested that this investment will pay back in 2.36 years. Given that the demand of LPG is on the increase and therefore, this LPG plant will be a long term investment with a good return on investment