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Showing 1 to 17 of 17 for “"VHTR"”.
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An Effective Methodology for Thermal-Hydraulics Analysis of a VHTR Core and Fuel Elements
The Very High Temperature Reactor (VHTR) is a Generation-IV design in the conceptual pre-licensing phase for potential construction by 2030-2050. It is graphite moderated, helium cooled reactor that operates at an exit temperature of up to 1273 K, making it ideal for generating electricity at a …
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Air Ingress and Heat-Driven Flow Relaminarization in a Very High Temperature Reactor (VHTR)
<p>Very High Temperature Reactors (VHTRs) are one of six Generation IV reactors that have been proposed for DOE’s Next Generation Nuclear Plant. In addition to using gaseous coolants, VHTRs also display benefits of passive safety systems including intra-core natural circulation for heat removal in …
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Swirling jets for the mitigation of hot spots and thermal Sstratification in the VHTR lower plenum
The literature indicates that a prismatic-core very high temperature reactor can experience thermal stratification and hot spot issues in the lower plenum (LP). This research hypothesizes that the complex thermalhydraulic phenomena in the LP requires a sophisticated computational fluid dynamics …
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Oxidation behavior of very high temperature reactor (VHTR) candidate materials: 316l stainless steel, Alloy 617, and Incoloy-800H
High temperature nuclear reactors require alloys to perform well at temperatures around 1000 to 1400 K. The oxidation behavior of three high temperature reactor candidate materials, 316 L stainless steel, alloy 617, and Incoloy 800-H under different conditions were investigated in the present work. …
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Materiály pro reaktory IV. generace
… práce je popis vybraných reaktorů IV. generace – VHTR, SCWR a MSR z hlediska jejich materiálových požadavků s důrazem na reaktor VHTR. V práci je popsán základní princip vysokoteplotního reaktoru a jeho základní uspořádání konstrukčních částí z hlediska materiálového namáhání. Ve střední pasáži …
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The Effect of Coating Parameters On Advanced TRISO Fuels With Zirconium Carbide
… obtainable in the very high temperature reactor (VHTR) design. These problems include but are not limited to over pressurization of the kernel due to fission gas buildup as well as kernel migration, in the presence of a temperature gradient, known as the amoeba effect. To negate these problems a …
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Plenum-to-plenum heat transfer characteristics under natural circulation in a scaled-down prismatic modular reactor
… for a prismatic very high temperature reactor (VHTR). Using advanced heat transfer coefficient probe and T-thermocouples. The facility represents a scaled down prismatic modular reactor with a reference to High-Temperature Test Facility at Oregon State University (OSU-HTTF). The natural …
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Experimental study of natural convection heat transfer and gaseous dynamics from dual-channel circulation loop
… of the prismatic very high-temperature reactor (VHTR) such as plenum-to-plenum heat transfer and gaseous dynamics during natural circulation. Natural circulation of the coolant is the leading capability for VHTR to transport the decay heat from the core to the reactor vessel during accident …
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Analysis of U-Zr-C-O Quaternary System for Applications in Advanced ZRC Coated Triso Particles
… particles for Very High Temperature Reactor (VHTR) conditions to prevent kernel overpressurization and kernel migration has been proposed by several researchers. Analysis is performed incorporating first-principles thermodynamics along with out-of-pile experimental work. …
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High temperature creep-fatigue behavior of alloy 617 and alloy 230
The Very High Temperature Reactor (VHTR) is one of the Gen-IV reactor design concepts which embody a common goal of providing safe, longer lasting, proliferation-resistant, and economically viable nuclear energy. One of the biggest challenges in the research and development of Gen-IV reactor …
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Physics-Based 3D Multi-Directional Reloading Algorithm for Deep Burn HTR Prismatic Block Systems
… deep burn very high temperature reactors (DB-VHTRs) was developed and tested to meet DB-VHTR operation constraints utilizing a high fidelity neutronics model developed for this dissertation. The high fidelity automated neutronics model allows design flexibility and metric tracking in spatial …
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Coating Parameters of Zirconium Carbide On Advanced Triso Fuels
… of using very high temperature reactors (VHTR) as part of the next generation of nuclear reactors greatly depends on the tri-structural isotropic (TRISO) fuel particles reliability to retain both gaseous and metallic fission products created in irradiated UO2. Most research devoted to …
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Microstructural evolution and mechanical behavior in nickel based alloys for very high temperature reactor
… program, the Very High Temperature Reactor (VHTR) is the lead concept. Design and development steps are currently underway to construct a high-temperature reactor as the next generation nuclear plant (NGNP) at Idaho National Laboratory (INL). A major limitation of this system is the …
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The Deposition Characteristics of Zrc On Uo2 Kernels Produced For Advanced Triso Fuels In Gen-Iv Reactors
<p>Very high temperature reactors (VHTR) are capable of achieving temperatures up to 1000°C, allowing for increased plant efficiency, as well as the ability for using the process heat for hydrogen production and other commercial uses. However, the limits of operation of VHTRs are currently …
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Investigation of the hydrodynamics and scale-up of advanced TRISO nuclear fuel manufacturing using sophisticated measurement techniques
… of the Very-High-Temperature Nuclear Reactors (VHTR) extremely depend on the quality of the TRISO nuclear fuel coated particles. However, the coating of the TRISO particles is delicate process and impacted by the hydrodynamics of spouted beds. Therefore, in this work, we applied advanced …
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CFD Modeling and Simulation of Natural Circulation in Helium- Cooled Very High Temperature Reactors
… in helium-cooled Very High Temperature Reactor (VHTR) systems, focusing on the performance and validation of passive safety features under Pressurized or Depressurized Loss of Forced Cooling (P-LOFC or D-LOFC) events. An experimental facility inspired by the General Atomics 350 MWt Modular High …
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Helium-Air mixing in simulated reactor cavities of Very High Temperature Reactors
… <p>Very High Temperature Reactors (VHTRs) and High Temperature Gas Reactors (HTGRs) are Generation IV gas reactors that promise to deliver high temperature process heat and efficient electricity for both industrial and commercial purposes. They have a high level of inherent passive …