Sürdürülebilir Kalkınma Amaçları
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- ArticleAçık Erişim2023INVESTIGATION OF THE USE OF CALCIUM CARBONATE AS NANOPARTICLES IN NUCLEAR REACTORS
Uzun, Sinem; Genç, Yasin; Acir, Adem
In this study, calcium carbonate (CaCO3) 3 ) was considered as nanoparticle. In the first part of the study, half-value layer (HVL) and mean free path (MFP) values, which are radiation shielding parameters, were investigated in determined energy ranges by Phy-X open access software. At increasing energy levels, the HVL value reached approximately 10 cm, while the MFP value reached approximately 17 cm. In the second part of the study, the reactor core geometry was modeled with the MCNP code and then the relative power distribution values were determined. COBRA code input was prepared with the determined relative power distribution values and thermal analyzes were made. These analyzes were performed for three different nanoparticle ratios. As a result of the analysis, the temperature value at the end of the channel was 613 K when only water was used as a coolant, while the temperature value at the end of the channel was 611.19 K when 0.03% nanoparticles were used. Although the coolant temperature increased with the nanoparticle ratio, it was observed that the temperature decreased when only water was used.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2021Investigation of Neutronic and Thermal Performance Using UGD and MOX Fuel in VVER-1000 Nuclear Power Reactor
Uzun, Sinem; Genç, Yasin; Acir, Adem
When examining the safety and design features of nuclear power reactors, its thermal performance in addition to neutronic characteristics is important. In this study, the neutronic and thermal performances of VVER-1000 reactor with two different fuel assembly arrangements were examined. Those fuel assemblies named as YD1 and YD2 are composed of 3.7% enriched LEU and 3.6% enriched LEU with 4% Gd2O3 uranium-gadolinium (UGD) and 2%, 3%, 4.2% Pu and 3.6% enriched LEU with 4% Gd2O3 (MOXGD), respectively. The effects of using UGD and MOXGD fuel assembly arrangements on criticality and isotope transformations according to burnup rate were investigated by means of MCNP5 and MONTEBURNS2.0 nuclear code, correspondingly the temperature and enthalpy changes of the coolant along the hot channel were examined with the help of the COBRA-IV PC thermal analysis code. The results obtained from this study were compared with similar studies in the literature and it was observed that the obtained findings were in accordance with the literature.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2021Investigation of thermal performance of aluminum nanoparticle coolant in vver-1000 reactor
Uzun, Sinem; Genç, Yasin; Acir, Adem
Thermal analysis is of great importance when examining the safety and design features of nuclear power reactors. The aim of this study is to examine the effect of pure water and coolant containing Al2O3 nanoparticles on thermal performance of VVER-1000 nuclear reactor. In this study, the VVER-1000 reactor is in steady state and BOC (begining of cycle) condition, relative power density distributions for UO2 fuel with 3.7% enrichment were obtained with the MCNP code and then, thermal analysis were made with the COBRA code and DNBR value, which is very important for the safety criteria of the reactor, was examined. In addition, with the COBRA code, thermal values such as temperature, enthalpy, density, and temperature values of the fuel and clad regions, which are of great importance for the reactor, were calculated. As a result of the analysis, it was determined that the most efficient coolant is 0.1% Al2O3 fluid in the heat transfer of the reactor.
RDL Kalıcı Kaydıİncele - ArticleYalnız künye2021Experimental investigation of thermal energy storage efficiency using fin application with phase change material (pcm) under solar radiation
Acir, Adem; Canli, Mehmet Emin; Ata, Ismail; Uzun, Sinem; Tanürün, Himmet Erdi
In this paper, the energy storage behavior of the thermal energy storage unit (TESU) using phase change material (PCM) and copper fi ns under artifi cial solar radiation was analyzed experimentally. The experimental tests of the TESU were performed at three diff erent fi n numbers (n = 3, 5, and 7) and fi n thickness (t = 1, 1.5, and 2 mm) under variable solar radiations (q = 800, 900, and 1000 W/m2). The stored thermal energy of each TESU was calculated and compared with solar energy coming from a solar lamp. The highest thermal energy storage effi ciency was computed as 95.08% in Type-VIII (n = 7, t = 1 mm) TESU below 1000 W/m2 solar fl ux. The thermal energy storage effi ciency enhancement ratio (TESEER) was defi ned to understand the eff ects of n and t of the thermal energy storage effi ciency of TESUs. The highest TESEER was calculated as 1.68 in Type-VIII (n = 7, t = 1 mm) TESU below 1000 W/m2 solar radiation. In conclusion, the TESEER values were decreased with increasing fi n thickness, whereas its values were usually increased with the increase number of fi ns.
RDL Kalıcı Kaydıİncele - ArticleYalnız künye2021Evaluation of the al/, cu/, si/, ag/water nanofluid effects on heat transfer characteristics in vver-1200 loaded with plutonium-thorium-based fuel
Genc, Yasin; Uzun, Sinem; Acir, Adem
This study is aimed at investigation of the potential effects of various nanoparticles used in certain properties and ratios in the coolant of VVER-1200 power plant on thermal hydraulic performance. Criticality and thermal hydraulic analysis have been performed by using MCNP and COBRA-IV/PC code, respectively. The fuel ratio has been selected as 90% ThO2 + 10% reactor grade (RG)-PuO2. Al, Cu, Si, and Ag nanoparticles in proportions of 0.01% and 0.1% by volume have been mixed with reactor coolant water. The effects of adding nanoparticles into the coolant at two different ratios on the reactor criticality, departure from nucleate boiling ratio (DNBR), and thermal hydraulic performance have been investigated. It is observed that by adding nanoparticles into the coolant, the temperature rise along the hottest channel is higher compared to the case when only water is used as the coolant, whereas the criticality and DNBR have shown a decreasing trend. It can be concluded that combination of fuel made up of 90% ThO2 + 10% RG-PuO2 and nanofluid containing 0.1% volumetric ratio of Si nanoparticle could be used in VVER-1200 nuclear power plant and this combination could contribute to augmentation of thermal efficiency of the plant.
RDL Kalıcı Kaydıİncele - ArticleAçık Erişim2020Investigation of Criticality and Relative Power Density Distribution in VVER-1000 Nuclear Power Reactor
Genç, Yasin; Uzun, Sinem; Acir, Adem
One of the most important elements of the design and safe operation of nuclear power reactors is the examination of the criticality and relative power density distribution. In this study, the neutronic performance analysis of the VVER-1000 containing the critical and relative power density distribution was calculated with the help of the MCNP neutronic code. Neutronic calculations were performed for four different fuel types. As a result of the calculations for each fuel assembly, criticality and relative power density distributions were obtained in the reactor core. The results obtained in this study were compared with the literature and it was seen that the critical and relative power density distribution values were similar.
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