共查询到17条相似文献,搜索用时 171 毫秒
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采用通用的CFD NHT软件PHOENICS 3 2和BFC计算网格生成技术 ,对ADS靶件束窗下方有无导流板两种靶件结构冷态下的流场进行数值模拟。描述了靶区流场数值模拟的方法 ,给出了流场数值模拟的结果 相似文献
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散裂靶是加速器驱动的次临界系统(ADS)的重要组成部分,有窗散裂靶是唯一经实验验证、测量的液态金属高功率散裂靶,研究有窗靶内工质的流动对散裂靶的设计优化有重要意义。本文以水为工质对有窗靶件进行了可视化实验及数值模拟研究,实验采用粒子图像测速法对靶件可视化部分进行速度场测量,同时利用计算流体力学软件FLUENT对靶件流场进行数值模拟。通过5种湍流模型(标准k-ε模型、RNG k-ε模型、Realk-ε模型、SST k-ω模型、RSM模型)在不同流速下的模拟结果与实验结果的对比分析,表明采用RNG k-ε模型并结合相应的壁面函数能较准确模拟有窗靶内的流动。 相似文献
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在加速器驱动系统(ADS)中,真空质子束流管出口端为一半球面质子束窗,用于隔离束流管和散裂靶。质子束窗表面热负荷很高,有效冷却质子束窗,从而提高靶件寿命和系统安全性是靶件设计的关键。 采用PHOENICS 3.2程序对ADS靶件冷态下的流场进行数值模拟。在贴体坐标(BFC)下生成计算网格,对靶件束窗下方有无导流板时的靶区流场进行了计算。当体积流量为10m3/h时,流体向下流动进入中央流道(靶区)之前发生边界层脱离,并在质子束窗下方两侧形成一对对称的旋涡。两旋涡在靶区中央重叠,形成一股向上较强的回流。这股回流沿质子束窗 相似文献
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冷却剂自由界面形态的形成和控制是加速器驱动的次临界系统(ADS)无窗靶件设计的关键技术之一。采用水介质对无窗靶件模型的自由界面特征进行了实验和数值研究。实验中采用激光诱导荧光的示踪方法实现了流场的可视化,得到Re=30000~50000范围内的自由界面和可视化流场。在高Re工况下,流场中出现大尺度的非稳定涡结构,随着Re的降低,流场中涡结构的紊乱程度增加。分别采用大涡模型(LES)和两方程动能-特征耗散率模型(kω-SST)对无窗靶件实验工况进行了数值分析,计算结果表明,LES能较好地模拟实验中所得的流场现象和界面特征。 相似文献
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采用通用的计算流体力学(CFD)软件PHOENICS 3.3和BFC计算网格生产技术,对加速器驱动次临界系统(ADS)靶件的流场进行数值模拟计算。结果表明:束窗下方导流板起引导流体沿束窗表面流动的作用,消除了束窗两侧下方较大的旋涡,对于改善束窗附近流体的流动结构、提高束窗表面及散裂靶的换热,效果显著。 相似文献
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《Journal of Nuclear Science and Technology》2013,50(10):1289-1299
This paper describes loss of coolant accident (LOCA) analyses of the Supercritical-pressure Water-Cooled Fast Reactor (Super Fast Reactor). The features of the Super Fast Reactor are high power density and downward flow cooled fuel channels for the improvement of the economic potential of the Super Fast Reactor with high outlet steam temperature. The LOCA induces large pressure and coolant density change in the core. This change influences the flow distribution among the downward flow parallel channels. It will affect the safety of the Super Fast Reactor. LOCA analysis of Super Fast Reactor is important to understand the safety features of the Super Fast Reactor. Keeping the flow rate in the core is important for the safety of the Super Fast Reactor. In LOCA, it is difficult to maintain an adequate flow rate due to the once-through coolant cycle and the downward flow cooled fuel assemblies. Therefore, the early actuation of the Automatic Depressurization System (ADS) and reduction of the maximum linear heat generation rates of the downward flow seed fuel assemblies and Low-Pressure Core Spray (LPCS) system are necessary for the Super Fast Reactor to cool the core under LOCA. Analysis results show that the Super Fast Reactor can satisfy the safety criteria with these systems. 相似文献
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Kairat Ismailov Masaki SaitoHiroshi Sagara Kenji Nishihara 《Progress in Nuclear Energy》2011,53(7):925-929
A feasibility study on natural uranium spallation target in accelerator-driven system (ADS) for minor actinide (MA) transmutation was performed. As a result of comparative study of uranium and lead-bismuth (PbBi) targets in the bare case without blanket surrounding, it was found that uranium target had better neutron generation performance, but limited by the geometrical size due to high neutron absorption in 238U. In ADS for MA transmutation, uranium used as target instead of PbBi also absorbs neutrons passing the target area.More realistic concept of pin type uranium spallation target cooled by liquid PbBi was considered aiming at enhancing spallation target performance in terms of neutron generation efficiency and operation temperature. The uranium pin target design had nothing better effects on neutron balance of such system than a conventional PbBi target in ADS and it was concluded that uranium target was not suitable for the full-scale ADS. 相似文献
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Wei-Feng Yang Chengwen Qiang Fei Wang Long Li Weiping Deng Xueying Zhang 《Journal of Nuclear Science and Technology》2013,50(12):1381-1392
The relationship between flow field characteristics and geometrical structures is an important issue in designing liquid metal spallation target for accelerator-driven sub-critical system (ADS). Upward spiral flow target (USFT) is a new type ADS windowless target in which an impeller is employed to generate upward spiral flow and regulate internal flow field. The impeller comprises a central shaft and several identical blades, and its geometry is very crucial for designing the target. In this paper, series models with different geometric parameters of the shaft and the blades are simulated by ANSYS CFX to analyse the distributions of internal flow field and the dimensions of stagnation zone in USFT. The results show that the shaft plays a primary role in guiding the upward flow while the blades are significant for generating the spiral flow. Finally, an optimized model with preferred geometric parameters is obtained by comparing the overall simulation results. The whole research has foundational signification for further studying USFT. 相似文献
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Chungho Cho Yonghee Kim Tae Yung Song Yong-Bum Lee 《Nuclear Engineering and Design》2008,238(1):90-101
A spallation target system is a key component to be developed for an accelerator driven system (ADS). It is known that a 15–25 MW spallation target is required for a practical 1000 MWth ADS. The design of a 20 MW spallation target is very challenging because more than 60% of the beam power is deposited as heat in a small volume of the target system. In the present work, a numerical design study was performed to obtain the optimal design parameters for a 20 MW spallation target for a 1000 MWth ADS. A dual injection tube was proposed for a reduction of the lead–bismuth eutectic (LBE) flow rate at the target channel. The results of the present study show that a 30 cm wide proton beam with a uniform beam distribution should be adopted for a spallation target of a 20 MW power. When the dual LBE injection tube is employed, the LBE flow rate could be reduced by a factor of 7 without reducing the allowable beam current. 相似文献
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颗粒流动广泛存在于自然现象和工程应用中,无论是山体坍塌还是工程上球床模块式高温气冷堆和中国科学院近代物理研究所提出的新型流态固体颗粒靶概念。本文基于适用于处理大变形问题的物质点法(MPM),采用μ(I)流变模型,实现了用连续性方法模拟密集颗粒流动的计算框架,并模拟了颗粒坍塌实验和漏斗流动现象,数值模拟结果与实验结果、DEM计算结果均吻合较好。本文采用的连续性本构和MPM能有效模拟密集颗粒流动。可在本文探究的连续性方法模拟密集颗粒流动的框架基础上,完善边界条件和本构模型,为用连续性方法处理大量颗粒的工程问题提供借鉴。 相似文献